Pigment Wrangler // Striking Palette

While copies of spells in zones other than the stack cease to exist when state-based actions are checked, this does not apply to copies of prepare spells in exile that were created as a creature became prepared.

If a spell with a converge ability is copied, no mana was spent to cast the copy, so the number of colors of mana spent to cast the spell will be zero. The number of colors spent to cast the original spell is not copied.

If a prepared creature stops being a creature, it will still be prepared, and the copy of its prepare spell will remain in exile. That permanent's controller will still be able to cast it. The same is true if a prepared creature becomes a copy of something else, even if it's then a permanent without a prepare spell.