I just posted this fix in another thread, might help some people here too:
So I know this is an old bug, but I'm currently playing through and ran into this, and found a fix for those of you who can't get the config fix to work and are on controller. To clarify Im playing on PC with and Xbox One controller at 60fps on fullscreen. I tried the config fix and it worked, but only for keyboard & mouse, still wasnt working on the controller. I noticed that if you press the trigger down immediately, axii will just stun. For puppet, what is working for me, is compressing the trigger about halfway. Idk why it works but it does. I hope this helps someone with the same problem.
This worked! Thanks!
I had the same general setup and issue: "PC with and Xbox One controller at 60fps on fullscreen" and the alternate axii sign would not cast. But pressing the trigger part way worked first time.