ToB: Maneuvers known and multiclass adepts

[PairO'Dice Lost]

There's no requirement stated anywhere that you must know a maneuver from a given class--and given that you can't learn a maneuver more than once, as Godskook pointed out, it would cause problems for a few things if maneuvers known were tracked separately. So it's all but guaranteed that it works, but it's not technically RAW.

And yes, Adaptive Style works for all of your maneuvers.