kono sekken ha nioi ga tuyosuginai node, mainiti tukaiyasui.

This is a very common question.

• この石けんは sets this soap as the topic: As for this soap...
• 匂いが強すぎない says something about one feature of the soap: its smell is not too strong

So the structure is roughly:

• この石けんは = as for this soap
• 匂いが = the smell
• 強すぎない = is not too strong

A natural way to understand it is:

• As for this soap, its smell is not too strong, so it is easy to use every day.

Here, が marks 匂い as the thing that has the property 強すぎない.

強すぎない is made from three parts:

• 強い = strong
• すぎる = to exceed, to be too much
• ない = negative

Step by step:

1. 強い → 強
2. attach すぎる → 強すぎる = to be too strong
3. make it negative → 強すぎない = not too strong

So this does not mean simply not strong.
It means not excessively strong.

That nuance is important:

• 強くない = not strong
• 強すぎない = not too strong

The second one suggests the smell may still be present, just not overwhelming.

They are similar, but not the same.

• 強くない = not strong
• 強すぎない = not too strong

With 強すぎない, the speaker is saying the smell is at an acceptable level.

That is why it fits well with 毎日使いやすい.
The idea is:

• the soap does have a smell,
• but the smell is not excessive,
• therefore it is easy to use every day.

If the sentence used 強くない, it would sound more like the smell is simply weak.

Both ので and から can mean because/so, but the nuance is a little different.

• ので often sounds a bit softer, more explanatory, and more objective
• から can sound a bit more direct or personal

In this sentence:

• 匂いが強すぎないので、毎日使いやすい。

ので gives a calm explanation:
Since the smell isn’t too strong, it’s easy to use every day.

If you used から, it would still be correct:

• 匂いが強すぎないから、毎日使いやすい。

That sounds a bit more straightforward.
Both are natural, but ので suits product descriptions and neutral explanations very well.

使いやすい is built from:

• 使う = to use
• verb stem 使い
• やすい = easy to do

So:

• 使う → 使い
• 使い + やすい → 使いやすい

This pattern is very common:

• 読みやすい = easy to read
• 書きやすい = easy to write
• 分かりやすい = easy to understand
• 使いやすい = easy to use

So 毎日使いやすい means easy to use every day.

毎日 means every day, and here it works adverbially, telling you when / in what kind of repeated situation the soap is easy to use.

So:

• 毎日使いやすい = easy to use every day

Japanese often places time expressions like 毎日, 今日, 明日, いつも before the main predicate.

You can think of it as modifying the whole idea of 使いやすい, not just the verb 使う by itself.

Yes, in a sense.

Japanese often leaves out things that are understood from context.
After talking about この石けん, the sentence does not need to repeat it.

So the full idea is:

• この石けんは、匂いが強すぎないので、毎日使いやすい。
• As for this soap, because its smell is not too strong, it is easy to use every day.

In English, you often need to repeat the subject more clearly.
In Japanese, once the topic is established with は, it is often left understood in the rest of the sentence.

Both can relate to smell, but they have different nuances.

• 匂い is more neutral and can be pleasant, noticeable, or simply a scent/smell
• 臭い often has a negative nuance, more like bad smell or odor

For soap, 匂い is more natural because the smell is not being described as unpleasant, just strong or not too strong.

So:

• 匂いが強い = the scent/smell is strong
• 臭いが強い could sound more negative, like it smells bad or too odor-heavy

石けん is commonly written this way in Japanese.

You may also see:

• せっけん in all hiragana
• less commonly, full kanji forms in certain contexts

For everyday writing, 石けん and せっけん are both common.

The reading is:

• 石けん = せっけん

Learners often wonder why it is not fully in kanji.
The answer is that some words are conventionally written in a mixed style because that is what is easiest and most familiar for readers.

Here, 匂い is read におい and it is a noun meaning smell / scent.

It is related to the verb:

• 匂う = to smell, to give off a scent

So:

• 匂い = smell, scent
• 匂う = to smell / to have a scent

In this sentence, it is definitely the noun:

• 匂いが強すぎない = the smell is not too strong

Not exactly.

強すぎない specifically means not too strong, not just not very strong.

That is because すぎる always adds the idea of excess:

• 多すぎる = too many
• 高すぎる = too expensive / too high
• 熱すぎる = too hot
• 強すぎない = not too strong

So the sentence is evaluating the smell against a reasonable limit.
It is saying the smell stays within a comfortable range.

It is in plain style.

You can tell because it ends with:

• 使いやすい
• not 使いやすいです

Also:

• 強すぎない
• not 強すぎません

A polite version could be:

• この石けんは匂いが強すぎないので、毎日使いやすいです。

Or even more fully polite:

• この石けんは匂いが強すぎないので、毎日使いやすいです。

The original sentence is natural for casual writing, product comments, reviews, or neutral explanatory text.

この means this and must be followed by a noun.

So:

• この石けん = this soap

The basic set is:

• この = this ... near the speaker
• その = that ... near the listener or already mentioned
• あの = that ... over there, away from both

Important:

• この cannot stand alone
• if you want to say this one, you would use これ

So:

• この石けん = this soap
• これは石けんです = this is soap

Japanese normally does not use spaces between words in ordinary writing.

The sentence would usually be written like this:

• この石けんは匂いが強すぎないので、毎日使いやすい。

Spaces are often added in teaching materials to help beginners see the word boundaries more clearly.

So the spaced version is for learning convenience, not standard native formatting.

Yes, that is a very natural English translation.

Just remember that the Japanese structure is slightly more like:

• As for this soap, the smell is not too strong, so it is easy to use every day.

In English, we often make it smoother by saying:

• This soap doesn’t have too strong a smell, so it’s easy to use every day.
• This soap isn’t too strongly scented, so it’s easy to use every day.
• This soap doesn’t smell too strong, so it’s easy to use every day.

All of these capture the basic meaning well.