Here you can see a small representative comparison for yourself:
In general, pictograms consisting of symbols on a square plate are lighter in color and slightly shiny. Everyday objects have had their outlines and gradients removed, giving priority to flatter shapes. Buildings, clothing, food, travel, sports and much more have been completely redesigned. Also, for consistency, some people’s emojis have been adjusted (to match the redesigned scissors emoji counterparts), like the haircut emoji scissors.
Move the slider left or right to compare the old emoji with the new style.
Nothing has been announced about when these redesigned emojis will be introduced on Android or Chrome OS, and it seems that none of them are included. New 2021 proposal — But with Android 12 coming up, it’s nice to see it work right away.
On the more subtle side, we found face tweaks, including the open eyes of the mask emoji (probably better suited to show a sick person as well as to encourage preventative masking). To my eyes, the overall aesthetic seems to be back in the direction of the old Android emoji, back to a flatter, almost blob-like playful style.