Beszélünk az esetleges késésről.

Beszélünk is the 1st person plural present tense form of beszél: we speak / we are talking.

In this sentence, with -ról/-ről, it means we are talking about something.

So:

• beszélünk = we talk / we are talking
• beszélünk valamiről = we are talking about something

Depending on context, it could also sometimes be understood as we will talk, but the basic form itself is present tense.

Hungarian usually does not need subject pronouns unless you want extra emphasis or contrast.

The ending -unk / -ünk already tells you the subject is we.

So:

• beszélek = I talk
• beszélsz = you talk
• beszél = he/she talks
• beszélünk = we talk

You could say Mi beszélünk... for emphasis, but normally mi is omitted.

Hungarian has two forms of the definite article:

• a before a consonant sound
• az before a vowel sound

Here the next word is esetleges, which starts with a vowel, so the correct form is az.

Important: the article looks at the next word, not necessarily the main noun.
So even though késés starts with k, you still say:

• az esetleges késés

because esetleges comes right after the article.

Here esetleges means possible, potential, or maybe happening.

So az esetleges késés means:

• the possible delay
• a potential delay

A useful warning: esetleges is not the same as English eventual.
It usually means something more like possible or contingent, not final or ultimate.

Because Hungarian adds a case suffix to the noun.

The base noun is:

• késés = delay

The ending:

• -ról / -ről = roughly about, or in other contexts off/from

With the verb beszélni, Hungarian uses this case to express about:

• beszélni valamiről = to talk about something

So:

• késésről = about a delay / about the delay

The form is -ről rather than -ról because of vowel harmony: késés has front vowels, so it takes the front-vowel form.

Késésről is in the delative case.

The delative ending is:

• -ról / -ről

Its core physical meaning is something like:

• off of
• from the surface of

But with many verbs, it has an idiomatic meaning. With beszélni, it means about.

So in this sentence, you should learn the whole pattern:

• beszél valamiről = talk about something

That is more useful than trying to translate the suffix literally every time.

Because az esetleges késésről is not a direct object.

Hungarian uses the definite conjugation only when the verb has a definite direct object.
Here the verb beszél does not take a direct object; it takes a complement with -ról/-ről.

So the structure is:

• beszélünk valamiről = we talk about something

Even though the noun phrase contains az, the verb still stays in the indefinite conjugation:

• beszélünk, not a definite-conjugation form

This is a very common point for learners.

Yes, you could also say Az esetleges késésről beszélünk.

Both are grammatical, but the emphasis can change.

• Beszélünk az esetleges késésről.
  A neutral statement: We are talking about the possible delay.

• Az esetleges késésről beszélünk.
  This puts more focus on what we are talking about, often with a contrastive or topical feel: It’s the possible delay that we’re talking about.

Hungarian word order is flexible, but not random. It often reflects topic and focus.

Yes, sometimes.

Hungarian very often uses the present tense for future meaning when the context makes it clear.

So:

• Ma beszélünk az esetleges késésről. = Today we are talking about the possible delay.
• Holnap beszélünk az esetleges késésről. = Tomorrow we’ll talk about the possible delay.

Without any time word or context, the most natural reading is usually we are talking / we talk.

In this sentence, yes, it is the natural choice.

Az esetleges késésről refers to a particular issue under discussion: the possible delay.

If you remove the article and say esetleges késésről, it sounds more general, less anchored, or more stylistically marked. In some contexts that can work, but in this sentence the version with az is the normal one.

So a learner should probably remember this sentence as:

• Beszélünk az esetleges késésről.

not as a bare-article-free phrase.

Then the noun would become plural, and the case ending would be added to the plural form.

• késés = delay
• késések = delays
• késésekről = about the delays

So the sentence would be:

• Beszélünk az esetleges késésekről.

That means We are talking about the possible delays.