I haven’t passed yet, but I’m also studying for it.
The official 2号 textbook is from 全国旅館ホテル生活衛生同業組合連合会 / 宿泊業技能試験センター. That’s the main material I’m using.

Also check the Prometric page and the Accommodation Industry Proficiency Test Center page, because the schedule and application rules can change.

One important thing: for SSW 2 accommodation, you need work experience proof. I heard 2 years of hotel experience is required when applying, so ask your company early.

I couldn’t find a good commercial textbook.
Most people I know used:

official textbook
past work experience
Japanese hotel manuals from their company
YouTube videos about hotel service Japanese
practice reading customer complaint examples

If your company has training materials for front desk, restaurant, safety, or customer service, ask if you can use them. Those are sometimes more useful than books.

For Japanese study, I think N3 reading level helps a lot.
N4 may be enough for simple work conversations, but SSW 2 questions can be long and situation-based.

Useful Japanese study materials:

TRY! 日本語能力試験 N3 文法から伸ばす日本語
Good for grammar and reading Japanese explanations.

新完全マスター N3 読解
Good if you are slow at reading long Japanese questions.

日本語総まとめ N3 読解 / 文法
Good for short daily study.

These are not accommodation textbooks, but they help with reading the test quickly.

I’m preparing for the same test too.

For SSW Accommodation 2, I think the most important material is the official textbook, “特定技能2号評価試験（宿泊分野）学習用テキスト”, published by 全国旅館ホテル生活衛生同業組合連合会. It’s available online and it’s made specifically for the Accommodation SSW 2 test.

But honestly, I don’t think the textbook alone is enough.
I’m also studying Japanese reading at around N3 level, because the questions can be long and situation-based. You need to understand what is happening in the hotel situation and choose the best response, not just memorize hotel words.

For Japanese study, I’m using things like 新完全マスター N3 読解 and TRY! N3. They are not SSW books, but they help with reading long Japanese questions faster.

Also, if you work in a hotel now, your actual job is really useful for studying. When there is a guest complaint, reservation mistake, lost item, allergy request, or emergency situation, try to think: “What should a senior staff or leader do here?” I think that kind of thinking is important for SSW 2.

So my study plan is basically:

official SSW Accommodation 2 textbook
N3 reading practice
hotel words from real work
asking Japanese staff when I don’t understand a phrase
reviewing real cases like complaints, safety, hygiene, and staff instruction

I haven’t taken the test yet, but this feels more useful than just buying random books.