Learn Hardcore Croatian: Za mene svatko ima pravo na svoje mišljenje i na miran razgovor. - For me everyone has the right to their own opinion and to a calm conversation.

In your sentence, Za mene svatko ima pravo… = “For me / In my opinion, everyone has the right…”.
You could replace it with Po meni or Po mom mišljenju without changing the meaning much, just the style slightly.

Why is the preposition za used in za mene, and which case does it require?

The preposition za almost always takes the accusative case.

ja (I) → mene (me) in the accusative
with za: za mene = for me

Here, za is used in its “opinion / personal point of view” meaning: “for me (personally)”. It’s the same pattern as:

za tebe – for you
za njega – for him
za nas – for us

What does svatko mean, and how is it different from svaki or svi?

All three relate to “every/all”, but they’re not interchangeable:

svatko = everyone / everybody (indefinite pronoun, singular)
- Svatko ima pravo… – Everyone has the right…
svaki = every / each (adjective, must modify a noun)
- Svaki čovjek ima pravo… – Every person has the right…
svi = all / everyone (pronoun, plural)
- Svi imaju pravo… – All (people) have the right…

In your sentence, svatko works like a standalone subject: “everyone” (singular), which is why the verb is also singular: ima, not imaju.

What case and grammatical role does svatko have in this sentence?

Svatko is in the nominative singular and it is the subject of the sentence.

Structure:

Za mene – introductory phrase (“for me / in my opinion”)
svatko – subject (“everyone”)
ima pravo – predicate (“has the right”)
na svoje mišljenje i na miran razgovor – prepositional object phrase (“to their own opinion and to a calm conversation”)

How does the phrase ima pravo na + [noun] work in Croatian? Can I say ima pravo za?

The fixed, idiomatic construction is:

imati pravo na + accusative = to have the right to [something]

Examples:

imam pravo na odmor – I have the right to a break
oni imaju pravo na obrazovanje – they have the right to education

In your sentence:

ima pravo na svoje mišljenje – has the right to their own opinion
i na miran razgovor – and (has the right) to a calm conversation

You do not say ima pravo za in this meaning.
Za might appear in other phrases with pravo (e.g. boriti se za pravo – fight for a right), but imati pravo na is the standard pattern for “have the right to”.

Why is it na svoje mišljenje and not na svoje mišljenju? What case is mišljenje?

After na in the construction imati pravo na, the noun is in the accusative case.

mišljenje (opinion) – neuter noun
nominative: mišljenje
accusative (same form for neuter singular): mišljenje

So:

na svoje mišljenje – “to one’s own opinion” (accusative singular)

Mišljenju would be dative/locative and would be wrong here.
The preposition na can take either locative or accusative, but:

with “right to” → na + accusative (na mišljenje)
with “on / in” (location) → na + locative (e.g. na mišljenju is possible in very specific contexts but means something else, not “to an opinion”)

Why do we use svoje and not njegovo or another possessive form? What is special about svoj?

Svoj is a reflexive possessive pronoun. It’s used when the possessor is the subject of the sentence.

In your sentence:

subject: svatko (everyone)
possession: svoje mišljenje (one’s own opinion)

So we say:

Svatko ima pravo na svoje mišljenje.
= Everyone has the right to their own opinion.

We do not usually say:

Svatko ima pravo na njegovo mišljenje.
That would sound like: “Everyone has the right to his opinion” (referring to some other male person’s opinion), not their own.

Svoj always agrees in gender, number, and case with the noun it modifies, not with the subject:

svatko – grammatical subject but doesn’t change svoj
mišljenje – neuter singular accusative
therefore: svoje mišljenje (neuter singular accusative form of svoj)

Why is it na miran razgovor and not na mirni razgovor or na mirno razgovor?

Razgovor is a masculine singular noun (conversation), and here it is in the accusative case (because of na + accusative).

The adjective miran (calm) must agree with razgovor:

masculine singular nominative: miran razgovor
masculine singular accusative (for inanimate nouns) is usually the same form as nominative:
- miran razgovor (nominative/accusative)

So:

na miran razgovor – correct (masc. sing. accusative)

The forms you suggested:

mirni razgovor – masculine singular nominative (can be used in some contexts, but here we need the standard miran with this word)
mirno razgovor – wrong, mirno is neuter or adverbial form, and doesn’t agree with razgovor

Why is na repeated before miran razgovor? Could we just say na svoje mišljenje i miran razgovor?

In Croatian, it’s more natural and clearer to repeat na:

na svoje mišljenje i na miran razgovor

This makes it obvious that both nouns depend on the verb phrase ima pravo na.

You can sometimes omit the preposition in very informal speech:

na svoje mišljenje i miran razgovor

but this sounds less careful and could momentarily confuse the listener. In writing and in standard speech, repeating na is preferred and stylistically better.

Can we move za mene to another position in the sentence? Would the meaning change?

Yes, za mene is a movable phrase that mostly affects emphasis, not the basic meaning.

Possible natural options:

Za mene svatko ima pravo na svoje mišljenje i na miran razgovor.
– Neutral, common: “For me, everyone has the right…”
Svatko, za mene, ima pravo na svoje mišljenje i na miran razgovor.
– Puts more focus on svatko and marks za mene as a side comment.
Svatko ima, za mene, pravo na svoje mišljenje i na miran razgovor.
– Slightly unusual but still understandable; za mene sounds like a parenthetical comment.

What would sound odd is putting za mene at the very end:

Svatko ima pravo na svoje mišljenje i na miran razgovor za mene.
This can be misread as if “a calm conversation for me” were the object, which is not the intended meaning.

So, sentence-initial or after the subject is best: Za mene svatko… or Svatko, za mene, ima…

Is za mene really necessary, or can we just say Svatko ima pravo na svoje mišljenje i na miran razgovor?

You can absolutely drop za mene:

Svatko ima pravo na svoje mišljenje i na miran razgovor.
= “Everyone has the right to their own opinion and a calm conversation.”

Without za mene, the sentence sounds more general / objective, like a statement of principle.

With za mene, it sounds more subjective, explicitly showing that this is your personal stance or opinion:

Za mene svatko ima pravo…
= “As far as I’m concerned, everyone has the right…”

How would I say the opposite idea, like “In my opinion, not everyone has the right to their own opinion and a calm conversation”?

You can negate svatko in Croatian as follows:

Use ne
- verb and replace svatko with svatko nema → “not everyone has”:
- Za mene svatko nema pravo na svoje mišljenje i na miran razgovor.
  Literally: “For me, everyone does not have the right…”
  This usually implies “not everyone has this right” (some do, some don’t).
Or be more explicit with ne
- svatko:
- Za mene ne svatko ima pravo na svoje mišljenje i na miran razgovor.
  This sounds more marked and less natural.

Most natural is:

Za mene ne mora svatko imati pravo na svoje mišljenje i na miran razgovor.
– “In my opinion, not everyone has to have the right to their own opinion and a calm conversation.”

But the important point is: you keep the same structure (ima pravo na + accusative), and just handle the negation with ne before the verb (ima / mora imati, etc.).