Mixamo has it where you can adjust the length of a stride before downloading.
Also, you can adjust the punches from high to low, and the reactions from high to low.
Is it possible for Reallusion to have an update or a free tool (like accurig) to adjust
FBX, BVH and IC motions.
With the Mixamo punch motion, you can create many different animations from that one motion.
It's like getting new motions, but you are just adjusting the current animations.
That would be cool if Reallusion can do that. Mixamo did that years ago.

I have used motion modifier for a long stride, but the character leans backward while lunging forward. 
Every time I have used motion modifier, the motion never works properly. I know about motion modifier.
It may work better while standing than it does while walking. A lot of motions you can make good while standing.
The way motion modifier is set up and the way it actually works are 2 different things.

I've used MM to adjust the walk of an elderly person and found it to work quite well. This is in IC8.

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