the avatars had a pretty distinctive look to them, sort of 3d rendered, made with shaded shapes. you could mix and match clothing for your avatar to customize it
it was fairly simple in operation, the background was generally just a photograph and you could pick a place to stand around in it. it all ran in the browser, maybe it needed an applet like java or shockwave
i think i found it!
https://web.archive.org/web/20031125201719/http://chatpoint.com/
the layout is what i remember, and there's a link to a comic, which tracks with what i remember from the site.. but all images are broken, sadly
chatpoint was also used by other websites as i remember, and it looks like today it lives on in a remake: https://www.chatadventure.nl/
i've tried looking for it in https://display.archive.org/nl but if i search for "chat" i can only see one of the 327 results whereas the next 326 are black. "avatar" gives 6 results all unrelated