TextureRegion.cs.metaHow to fix this until the devs get around to it:
COPY(not move) the directory "com.esotericsoftware.spine.spine-unity@53ae86a025" from:
Then refresh Unity. It will create the missing .meta file automatically.
NB: When the devs fix this file, remember to remove the duplicate folder sitting in the Packages directory to fall back to Spine's official release.