if the move isnt in SW/SH, it wont let you transfer the pokemon to it to begin with... youd have to replace that move in the original game with something else to allow the transfer to even occur.. and im talking about legit moves, not even hacked ones.. if they didnt code a certain old move into sw/sh, they wont let you bring that pokemon over into the game...
I don't understand what you mean? I have transfered pokemon from my 3ds Sun/Moon/Ultra Sun/Ultra Moon/Alpha Saffire etc. to pokemon bank and from pokemon bank to Pokemon Home and from home to Sword/Shield and if they have moves that don't exist in Sword and Shield they have an sign that there are moves not possible in Sword/Shield, but the pokemon can just be transfered to the game (also pokemon from let's go Pikachu to home and then to Sword/Shield the same)..