For what it's worth, the remasters give us a little insight into how the films were animated. By messing up the illusion of life, we get to see some of the tricks used. The eyes are clearly their own layer, with the lids just being animated over them. And is Cera red underneath? Are the basic character shapes done in solid colors? I'm not an animator myself, so I'm not entirely sure why that would be a layer under her eye, but it'd be an interesting question to pose to the production teams.
We don't get a lot of behind the scenes info with the sequels, so I'll take what I can get, even if it's a silver lining on a storm cloud.
