When using any Vanilla Armor Trim template and any of the three Geode+ materials, the result has 'missing texture'.
Geode+ Trim templates work both with Vanilla and Geode+ materials.

When equipped, this is how it is rendered.

Minecraft 1.20.1
Fabric Loader 0.15.11
Fabric API 0.92.2
Geode+ 1.2.5

Relates to and found when investigating this issue with Elytra Trims:
kikugie/elytra-trims#63

More likely kikugie/elytra-trims#61 , but it is on the Geode+ side