I can confirm that you do not have to be crediting to any particular FF plan to get any of the benefits, so getting QFF baggage allowance while crediting to AA is fine and quite normal. As are any possible permutations, just be prepared to show proof of status. It is also possible to have 2 FF numbers in the same reservation, however sometimes this is done incorrectly (I always put in my WP status when crediting to AA on QF; bugs the hell out of some agents).