Legion Drop

Generally speaking Legion is good at killing infantry, good at killing moderately hard targets (like ARM 18 warjacks), and they can have some good assassination tricks. They tend to be fast, but not tough, and don't rely much on combos or support models, other than fury management. They're broadly similar to Retribution in how they play.

Both of your armies look like decent drops into Legion, as they can hit hard enough and accurately enough to drop the heavy beasts Legion likes to bring. Hylenna is probably a little bit better because she has a stronger ranged game so she's better able to counterplay the speed you're likely to see on the other side of the table. Just play safe with her and make sure she doesn't get assassinated.