Using multiple Sub instances with root motion does not behave as expected.
With both the parent and sub instances set to 'Root Motion from Everything':
In 4.22, too much root motion occurs.
In 4.24, no root motion occurs.
Open the attached project and SIE.
Observe that in 4.22 the ABP with sub instances results in an excess of root motion, while in 4.24 there's no root motion at all.
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-85657 in the post.