The left one I can move his arms on scene mode with my mouse.. The right one I cant.. Its stiff. And it has even more features like elbow and wrist tagged...
Here is video: https://streamable.com/z4yug2
This is because Baker, the right character, has triggered poses that are taking precedence over manual dragging. If you look in the triggers panel and turn the default off under his poses, you should be able to move him manually again. This is the case with a lot of characters - some creators just want triggered arm poses. But if you turn their default triggers off you should regain manual control again!