I made that profile. Most any FBX files have a rest pose as T-pose.
So I imported fbx from MoCapade to Blender (export Unreal without blend shapes option form MoCapade), switched to the Rest pose and exported without baking animation.
Then imported to CC, in Characterization tweaked bones to have the Unreal T-pose look more like an RL T-pose (hardest part - specifically for fingers).
And then mapped bones and saved 3dx profile as custom.
Regarding feet slide, I have more or less stable routine working with reach targets.
It is pretty much similar to Motion Correction, only manual where I have more control over it.
I have 2 same characters with same movement where I move feet of one character with mostly L/R Reach objects (actively using transition curves)
while having second character as a reference and trying to match planted foot without sliding.
I do not have a video of a process itself, but I have a video of a result.
And yes, although it's time consuming, the achieved result can be perfect with zero sliding.