Mirroring animation clip without mirroring root motion node?

Hey I usually animate one step in my motion cycles and then mirror them in states, but when I do that to running left or running right it ends up moving in a straight zigzag as the character's root node also gets mirrored

is there a way to specify/mask which bones get mirrored and which don't? preferably from within the animator as I also want to be able to mirror the root node under certain circumstances

note that my root motion node is a separate bonethat I manually animate for control