I think you hit the nail on the head with this. As you can see, the first of the list is a Emojii font I had to install to see emoji in Chrome. It’s totally wrong that it comes up as first choice for “sans”. Where is this declared?
$ fc-match -s sans |head
NotoColorEmoji.ttf: "Noto Color Emoji" "Regular"
DejaVuSans.ttf: "DejaVu Sans" "Book"
DejaVuSans-Bold.ttf: "DejaVu Sans" "Bold"
UPDATE: I followed a crappy guide to fix emoji in chrome that instructed to have this file in place: