Without converting to VRM, virtual cameras, face-tracking software, and metaverse platforms cannot read your character's skeleton or facial movements. Prerequisites for Successful Conversion

: Download and enable the VRM Add-on in Blender's Preferences.

: Run the export one last time to save your completed VRM. Why Convert to VRM? An Unbiased Review of the VRM File Format | by Hakanai

An open standard extension of glTF optimized for avatars. It standardizes bone mappings, humanoid constraints, facial expressions (blendshapes), first-person viewpoints, and physics for hair and clothing.