godot-blender-importer

This now a built-in feature of Godot Engine 4.0.

Blender Importer Addon for Godot

This addon for Godot will automatically import any .blend file in your project directory.

Changes to the file will be automatically picked up, and your scene updated.

TL,DR:

Add this addon to your Godot addons directory, activate it, and make sure the Blender path is correct in project settings.
Now Blender files in the project directory magically auto-import and auto-update

Longer Version:

You will need Godot 3.4 and Blender 2.93.5

Beware: Godot Engine through Steam has sandboxing issues. Try official versions on itch.io or Github.

Open this project in Godot Engine 3.4. (or add the addons directory to your project)
May not be needed: Go to Project Settings > Plugins and make sure the plugin Blend is activated.
May not be needed: Go to Project Settings > General > Filesystem > Import > Blender (or just search for blender at the top) and make sure the path to Blender is set. If Blender is in your global path (for example, if you use scoop to install Blender, or you are on Linux/Mac), you can just leave the default blender.
Open Blender, and save Blend files to the project folder. Create one directory per file (materials will be extracted, and might conflict with other materials if you have more than one file).
Switch to Godot, and see the Blender file getting auto-imported
From the imported file, you can now create an inherited scene (double click the file and Godot will propose to create an inherited scene for you).

If you change your Blender file, remember to close your inherited scene in Godot (without saving it), or else you won't be able to see the changes.

It seems the editor can sometimes hang on exit if scenes are left open and unsaved
If a scene is open, and the blend file is updated in blender, changes will not be reflected until the scene is reopened (known Godot limitation)