Quick answer: Godot 4 export fails despite templates matching version? Templates from a different build of the same version still mismatch - use templates from the same release archive.
Editor: 4.3.0-stable from official build. Templates: 4.3.0-stable from a custom build. Mismatch.
Use matching release archive
Download both editor and templates from the same release page. Mono and standard variants differ; same archive is the cure.
Or build custom templates
If you build editor from source, build templates from the same commit. Match by source, not version string.
Pin in CI
Build script pulls both from one URL. Mismatch becomes impossible.
“'Same version' isn't 'same build'. Templates and editor must match by build, not by tag.”
If you build editor or templates from source, both must come from the same commit. The mismatch is silent and frustrating.