How to tell direction of rotation using X2 hall effect sensors?

Not when the pulses don't overlap. On both A edges the B input will be LOW. On both B edges the A input will be LOW.

I can see how it might work if the pulses overlapped. The "rising" edge of A would have B LOW in one direction and B HIGH in the other. The "falling" edge would have the opposite.

Perhaps the OP has the option to have the sensors close enough together that the pulses overlap.