Double Fusion is a Normal 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, Double Fusion is Unlimited.
YGOPRODeck lists Double Fusion for these formats: TCG, OCG, Master Duel.
Double Fusion belongs to the Fusion archetype—use that tag when searching for engine pieces and tech options.
A listed print of Double Fusion appears in Doom of Dimensions (DOOD-EN100) at Super Rare rarity.
Among markets shown on this page, the lowest listed snapshot for Double Fusion is about $0.21 on TCGPlayer (prices change frequently).
