Please post inside the comments of the addon itsself, it's easier for the dev to answer and help then.
https://www.esoui.com/downloads/info...nded.html#info
Edit:
I saw you already did this, good.
Btw: Afaik the combat text was not changeable or maybe was changeable in the past. If I'm not informed wrong it is not possible to access and change this via the API anymore.
Maybe exchanging total fonts in the game with others would reflect into a changed font at the scrolling combat text as well though. Not sure how and what LUI extended was able to do there.