Star Changer is a Quick-Play Spell Card.
Spell Cards are usually activated from the hand on your turn unless their type gives another timing window.
On the current TCG and OCG Forbidden & Limited lists tracked here, Star Changer is Unlimited.
YGOPRODeck lists Star Changer for these formats: Common Charity, TCG, OCG, Master Duel.
A listed print of Star Changer appears in 2-Player Starter Set (STAX-EN035) at Common rarity.
Among markets shown on this page, the lowest listed snapshot for Star Changer is about $0.04 on Cardmarket (prices change frequently).
