I don't think you can be certain of recognizing the mixes.
That mixed hen, bred with a Spitzhauben rooster, does have the potential to produce chicks with proper Spitzhauben-type combs, crests, etc. Those traits may not all be in each chick, but any single trait has a good chance of being in at least some of her chicks.
Probably some of her chicks will be easy to spot, but some may be difficult or impossible. You could consider penning her up while you are collecting eggs for hatching, to be sure that you know which eggs are hers and just don't incubate them. Or do incubate her eggs, but only in situations where you will know which chicks hatch from those eggs and then you mark her chicks or raise them separately from others, at least until they are old enough that you are confident of recognizing them.