Hello, I made few animations before making the armature of my human inverse kinematics friendly but from now on I want to make the armature inverse kinematics friendly but as soon as I did that the animations go crazy, is it possible to do this?
Use a different set of bones. Then you can switch them between FK which you have and IK the new ones. If you don’t know how, check out Humane Rigging. I think you should be able to find it on you tube or better yet buy it for 10 bucks a month on Blender.org.
Did you know how to create a FK IK switcher in blender?