I don't believe there's an indicator, so you'll have to remember the skill and what it does unfortunately. However, in general, fist skills move the enemy, while spear ones move the user. Some characters have innate skills that can move others or themselves around (Nekomatas and Skeletal Dragons can do the former while Adell, Tink, Ninjas and Yukimaru can do the later. Probably more that escapes my mind atm).

edit: yup, after checking a guide there were quite a few that I missed (mostly characters/skills that I don't use often or at all), and most of them moved the user instead of the enemy. Comparatively, though, there aren't that many skills that can do either, and you most likely won't be using every single unit in the game, so you'll only have to remember some of them.