Depends on the nature of the disability I would say.

A neurological disorder of some sort or some other difference would likely not be curable but some sort of magical item could assist, rather than completely 'fix' the issue. It would be kind of fun to see how a high charisma character with autism handles things though.

Mobility issues could be routed around with enchantments and such or the use of some kind of frame or wheelchair even. Something fancy or something crudely constructed.

Typically no as far as my understanding, at least not without some serious magic like a true polymorph spell (a 9th level spell)

Of course then you have the difficulty of finding someone who not only knows the spell but is willing to use it on some random person