Emeritus of Truce // Swords to Plowshares

A creature with a prepare spell can't become prepared more than once at the same time. For example, Emeritus of Ideation is on the battlefield and is prepared. When it attacks, its last ability triggers. When that ability resolves, its controller may still exile eight cards from their graveyard, but doing so won't cause Emeritus of Ideation to become prepared a second time or create a second copy of Ancestral Recall in exile.

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.

Creating a copy of a creature's prepare spell in exile ignores copy exceptions applied to that creature that would affect the copiable values of that spell. For example, say a player casts Croaking Counterpart (a sorcery that says "Create a token that's a copy of target non-Frog creature, except it's a 1/1 green Frog.") targeting Goblin Glasswright. The token copy of Goblin Glasswright will enter prepared as a 1/1 green Frog creature, but the copy of Craft with Pride in exile will still be a red sorcery. The copy of Craft with Pride won't be green, a creature, or a Frog, and it won't have power or toughness.