Heya,
It will power it. Not perfectly. But it will work to an extent.
Thing is, the 5LE needs more power than the HE500 and the O2 is just barely able to truly properly power those.
For the 5LE, I would get a speaker tap adapter for your cable and get a speaker amplifier. I did it for my Hifiman's and it's better than my Lyr for the orthos. And cheaper.
Read here for more info. The amp is only $179 right now (ships free; Emotiva.com).
Very best,