The premium edition of Ever 17 (the one Hirameki released) added the swimsuit pictures (and maybe a few other CGs?), along with some of the other bonus materials - but definitely no H content. Ever 17 couldn’t really be an eroge, as the characters are given clear ages, most of which are under 18.
For their other titles that I’m familiar with, Animamundi (originally non-eroge) was edited a fair bit - I think a few of the guro shots were removed or darkened, and a few of the more sexual CGs were cropped. Maybe these cuts were ostensibly to avoid an AO rating, but having seen the full uncut CG set, I don’t think the game needed to be edited.
Yo-Jin-Bo looks like it was unedited (and it’s quite a good title as well - it’s a bit short and could do with a few more CGs, but the translation/humour (not entirely literal), voice acting, and the soundtrack are all very good (including 15 vocal tracks!)).
I think the version of Hourglass of Summer Hirameki released was the original PS2 one (hopefully without any edits) - there was a PC version of Hourglass produced which added a H-scene for all the winnable characters. Unfortunately, the Hirameki version is in the horrible animeplay DVD format.
I’m not sure if Piece of Wonder got edited at all - I haven’t really gotten that far into it yet.