Thanks for responding. I thought the multiselect was not working, however I think I have discovered a bug. Sometimes the click and drag method works, and sometimes it results in that. I managed to capture it working and not working on the same GIF. I tried to make it into an inline GIF but for some reason itchio didn't like me uploading, but there is a Google Drive link to that GIF. Thought click and dragging wasn't working at all, since I was getting that issue when I was using it.
https://drive.google.com/file/d/1WeeeO8afxj_2F0CqjKyphvbr_Xk6szYL/view?usp=share...
I tried to find a consistent way to re-produce it, but it seems to happen on random. Sometimes a releasing left click registers, and sometimes it doesn't register. I think it may have something to do with the positioning of the cursor, however so far in my attempts it seems random. This may be a hardware issue too, but I haven't really troubleshot that yet. But shift clicking always works, so thank you for bringing that up, I appreciate it.
In the GIF you can see I have quite a bit of bones and managing those in the timeline gets a bit tedious at times. So far I have an animation that I call t-pose, and I copy the key frames from that to get the whole skeleton key frames to other animations. For that, I wish there would be something that would help out. But it works, and I am able to animate.
Glad to see that replacing images onto the skeleton is as easy as that. My plan was to make a skeleton template and animate once, and just replace the images with character specific bits, so I can just animate once. Thank you for having an easy solution for that.