Humanotion - Free avatar pack, perfect for Notion
Boring Avatars - JavaScript library to generates SVG avatars based on text.
Humaaans - Mix-&-match illustrations of humans with a design library.
Avatar SDK - AI-powered 3D avatars from one photo
TinyFaces - Free crowd-sourced avatar gallery including Sketch plugin
Dollo - 300+ mix-and-match components to create your own avatar