watasi no itoko ha, nattou ha taberareru keredo, umebosi ha nigate da to iimasu.

Because each は is doing a slightly different job.

• 私のいとこは sets the main topic: as for my cousin
• 納豆は marks natto as a contrastive topic
• 梅干しは marks umeboshi as another contrastive topic

So the structure is roughly:

• As for my cousin,
• natto they can eat, but
• umeboshi they are not good with / dislike

This repeated は is very common when Japanese is comparing or contrasting items.

Both are possible.

• 私のいとこは = my cousin
• いとこは = my cousin / the cousin depending on context

Japanese often drops information that is already clear. If the speaker wants to make it explicit whose cousin it is, they include 私の. If that is already obvious, they may leave it out.

Also, いとこ does not tell you male or female cousin. Japanese usually leaves that unspecified unless it matters.

Normally yes:

• 納豆を食べる = eat natto

But here 納豆は is not just the object; it is being highlighted as a contrastive topic:

• Natto, they can eat
• but umeboshi, they are not good with

So は replaces the expected object marking to create contrast.

You can think of it as:

• neutral: 納豆が／を食べられる
• contrastive: 納豆は食べられる

This is very natural in comparison sentences.

Here it is potential, not passive.

• 食べる = to eat
• 食べられる = can eat / be able to eat

So 納豆は食べられる means:

• can eat natto
• or more naturally in context, is okay with natto

Japanese potential forms can sometimes look identical to passive forms, but context usually makes the meaning clear. Here, passive would not make sense.

食べられる is the standard form.

• standard: 食べられる
• casual spoken form: 食べれる

Many native speakers do say 食べれる in conversation, but in standard written Japanese and careful speech, 食べられる is preferred.

So this sentence uses the standard grammar.

けれど means but / although / though.

It connects two contrasting ideas:

• 納豆は食べられる
• 梅干しは苦手だ

So:

• can eat natto, but umeboshi is not liked / is difficult for them

Compared with some other forms:

• けど = more casual
• けれども = a bit more formal
• が = also can mean but in this kind of sentence

All of these can connect contrasting clauses, but けれど sounds very natural and neutral.

苦手だ has a slightly different nuance.

• 苦手だ = not good with; weak with; not fond of
• 嫌いだ = dislike
• 食べられない = cannot eat

So 梅干しは苦手だ does not necessarily mean a strong emotional dislike. It often suggests:

• the person finds it hard to handle
• they are poor with that food
• they do not really do well with it

With foods, 苦手 often sounds a bit softer and less direct than 嫌い.

Because 苦手 behaves like a noun / na-adjective, so it needs the plain copula だ in this quoted clause.

• 梅干しは苦手だ = umeboshi is something they’re not good with

This matters especially before と when quoting or reporting speech. The quoted sentence is in plain form, so:

• noun / na-adjective + だ
• i-adjective + no だ
• verb + no だ

For example:

• 静かだと言います
• 高いと言います
• 行くと言います

So 苦手だと言います is correct.

と marks the content of what is said, and 言います means say.

So:

• 梅干しは苦手だと言います
• (they) say that umeboshi is difficult for them / they don’t like umeboshi

More broadly, the whole quoted content is:

• 納豆は食べられるけれど、梅干しは苦手だ

Then と言います means:

• says that ...

This is an indirect quote.

That is standard Japanese reporting structure.

The content being quoted usually appears in plain form, and the reporting verb can still be polite.

So:

• quoted content: 納豆は食べられるけれど、梅干しは苦手だ
• reporting part: と言います

This combination is very common:

• A plain sentence + と言います

You would not normally say:

• 苦手ですと言います

because です／ます inside this kind of indirect quote is usually avoided unless you are intentionally quoting the exact polite wording.

The subject is understood to be the cousin.

Japanese often omits subjects when they are clear from context. Once the sentence begins with:

• 私のいとこは

the listener understands that the following comments are about the cousin.

So the sentence does not need to repeat:

• 私のいとこは納豆は食べられるけれど、私のいとこは梅干しは苦手だ

That would sound repetitive.

Yes, but the nuance would change.

For example:

• 私のいとこは、納豆が食べられるけれど、梅干しが苦手だと言います。

This sounds less contrastive and more like a plain statement about ability/preference.

The version with は on both foods strongly sets up a contrast:

• natto is okay
• umeboshi is not

So the original sentence is especially natural if the speaker wants to compare those two foods.

It can often be understood as a general or neutral report: my cousin says ...

Japanese non-past 言います does not have to mean only habitual present in the English sense. It is often used simply to report what someone says or has said in a general way.

If you wanted to emphasize a specific past event, you might say:

• と言いました = said

If you wanted to emphasize the current quoted state/result of what they have said, you might also see:

• と言っています

But と言います is perfectly normal here.

It is mostly a writing aid, not a required grammatical element.

• 私のいとこは、納豆は食べられるけれど、梅干しは苦手だと言います。

The commas help the reader follow the topic and contrast more easily. Japanese punctuation is somewhat flexible, especially in sentences with several topic markers or clauses.

So the commas improve readability, but the grammar works without them too.

A natural English rendering might be:

• My cousin says they can eat natto, but they’re not good with umeboshi.
• My cousin says natto is okay, but they don’t like umeboshi much.
• My cousin says they can handle natto, but umeboshi isn’t their thing.

A very literal breakdown would sound more like:

• As for my cousin, natto they can eat, but umeboshi they are bad with, (they) say.

That literal structure helps show the Japanese grammar, even though it sounds unnatural in English.