i changed the A-pose to a T-pose on the new character within the retargeting editor (followed the wiki documentation that was linked above). The animations transfer, but are pretty funky as the new mannequin has a wider chest, so hes arms clip his sides, and his legs are unnaturally far apart as he runs. I suppose further tweaking to the initial pose to more closely match the T-pose of the original character could remedy this to some degree, but I’m not an animator so I feel it’d prove somewhat fruitless.