I Know that the Beast, Sebastian and Pineocchio appear in aladdín and Belle appears in the hunchback of Notre Dame, but are there any others??

Scars Hyde appears in Hercules.

genie has a goofy hat

Lady and some other perros from Lady and the Tramp appear in 101 Dalmations. Pongo, Pegg, Jock (I think) and probably some other canine disney characters appear in Oliver and Co.