Presently, there is an imperfect solution for this issue.
Press your tilde (~) key two or three times, and you should eventually be gifted with floaty health bars that hover over all nearby demigods. I use this to keep track of my teammate's health when I play Sedna.
Note: the first time you press the tilde key, you'll get healthbars over demigods, minions, AND creeps. Which really isn't helpful in this scenario.
Just keep on pressing it until you only see healthbars over yourself and your fellow demigods.