Late reply, but tried implementing ICondition and copying some code over from ModLoadedCondition:
Getting an error for including the test() method since it is marked as deprecated, but forge still requires it to be implemented. Using Forge 1.18.2-40.1.51, if I'm missing anything let me know.
EDIT:
The mod will still compile and run fine since this isn't actually an error, but will need to know how to pass existing datagen recipes through the serializer since forge does not come with any functional examples by itself. Would still appreciate an answer on how to get rid of the deprecated method in case I am missing something obvious.