Up until now what I've seen her use are spells and one handed attacks. :)

If you use the skse and skyui, when you press esc there's a thing in that menu called Mod Configuratin Manager or MCM. Click that and another menu will open. Then, click on Sofia Follower and you'll get Sofia Settings and Stats. If you want her to use two handed set her combat class to light armour two handed and her combat style to two handed. She'll use a bow and a two hande sword or har wammer and she is quite deady with both.

Oops! War hammer.