Yeah, it's the kind of thing a video would really help to understand. The description didn't make it entirely clear what might be happening, and there's a good chance it's a conflict with another plugin. If you want to debug this until we find a definitive solution, you can add me on Discord. There you can send videos up to 10MB, and that might be a way for me to understand what's going on.
Viewing post in Kadajah's Damage Popup for RPG Maker MZ comments
I can hop in later and see about sharing this issue. honestly a lot of what I wanted is already handled and working as is. I was looking for a system to show my damage numbers with slightly more style (custom fonts, simple animations, and more color control plus Weakness and resistance) and this covers all of what I wanted despite visual bugs that are likely VisuStella related (in my experience so far this seems common and I'm not bothered by it).
Despite that I can still share my findings with you when I get time to join the discord. I have discord nitro so my video abilities should be pretty good there,