Can you run a reverse in flag football?
Yes. As many handoffs as you like behind the line.
Reverses and double handoffs are legal. The offense can hand off as many times as it likes, as long as every handoff happens behind the line of scrimmage, before the ball is carried past it and before possession changes.
Once a runner crosses the line, there are no more handoffs or pitches on that play.
IFAF Flag Football Rules 2023, R 7-1-5-a
None for a legal reverse. A handoff past the line: illegal handoff, 5 yards from the spot, plus loss of down (signal S19).

NFL FLAG and local leagues can differ. Check the rulebook your league plays.
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