Games Hub is reporting that AEW's inagural game FIght Forever is being delayed not due to development issues but due to ESRB rating issues. The goal of Yukes and AEW is for the game to have a Teen (T) rating. This will allow them to sell to a much younger audience. The current reports state that the amount of blood and violence in the game have it above the rating.
ESRB stands for Enterntainment and Software Rating Board. The ESRB was founded in 1994. It has five ratings two of which are above the T rating AEW wants for their games. Those two are the Mature and Adult. Hopefully it isn't a mini game that is keeping it from getting there as I know many fans are eagerly awating them.