Double Attack 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 Attack is Unlimited.
YGOPRODeck lists Double Attack for these formats: GOAT, OCG GOAT, Duel Links, Common Charity, Edison, TCG, OCG, Master Duel.
A listed print of Double Attack appears in Dark Revelation Volume 3 (DR3-EN220) at Common rarity.
Among markets shown on this page, the lowest listed snapshot for Double Attack is about $0.08 on Cardmarket (prices change frequently).
