タイトル : Anyone working in Japanese factories under SSW? How hard is the work actually?

I passed the exam recently and I’m looking at manufacturing jobs in Japan.
Some companies say “easy work” in ads, but I don’t really trust that

How hard is factory work in reality?
Is it mostly standing all day?
How much overtime is common?
Also, are dorms usually okay or very strict?

I’m especially interested in food factories or industrial product manufacturing.
Would like to hear real experiences before applying.