Even he could chose any form to show himself as, the Shaw form doesn’t make any sense to me.
FTFY
And frankly yes it does make sense. Hayden Anakin represents a character that Luke never knew, a character that became evil, and frankly makes the redemption less meaningful because it implies he’s reverting to his pre-evil self, not a redeemed man. And if you wanna frankly argue that unscarred Shaw never existed, neither did Anakin in those Jedi robes in both scenarios.