I think I got a workaround, if ya’ll are still having trouble. In your exported animation sequence asset, set retarget source and asset. I chose the same assets as the non-retargeted anim here, but it also worked fine when selecting pretty much any metahuman asset.
I’m not 100% sure, but it appears the warped proportions might match the standard Unreal Manny Skele (see pic below), my theory is that when baking an animation sequence for certain metahumans, it baking it to the wrong skeleton, and you jut have to re-target it back to a metahuman to correct the proportions.
L (retargeted anim) M (baked aset / no retarget) R (default Manny)