do he have an easy way to rest the spells to the ones we are supposed to if we change classes

i have a wizard wow was a swashbuckler and would like to have his spells

also it would be good to have in case we get a race change potion working

Currently no there is no automatic way to do it. After you change the class you can /level to get the new spells but you will still have the old spell I believe.