>>7193059Not him, but the one on the left is definitely the old one. The lack of double jointed elbows gives it away.
As far as who's doing the designs for newer HGUCs, I'm like 90% sure it's NAOKI heading the line as a whole. While the guy has certainly been influenced big Katoki, I think NAOKI's own style is showing through more these days, especially on kits like the GM Ground Type