Choonster

Yes, once you have data generation set up, it's a lot easier to add a line of code to your generator class than it is to copy, paste and edit 2-3 JSON files for each new item.

Minecraft 1.21.4 requires a new model definition file for each item, which you don't have. These can be created through Data Generation, specifically the ModelProvider, BlockModelGenerators and ItemModelGenerators classes.

https://forums.minecraftforge.net/topic/155182-trying-to-play-1201-in-multimc-with-forge-mods-but-this-error-all-the-time/

You can try their Ideas Portal, linked from the footer of their site.

You seem to be confusing Minecraft Forge (a mod loader, this site) with CurseForge (a mod distribution platform for Minecraft and other games). The two are unrelated, you probably want to take this feedback to CurseForge.

Forge only supports Java Edition, you'll need to ask elsewhere for Pocket Edition support. Also, don't post in unrelated topics. I've split your post into its own topic.

You're using the wrong FACING property in Mechanism#getStateForPlacement, BlockStateProperties.FACING instead of Mechanism.FACING, HorizontalDirectionalBlock.FACING or BlockStateProperties.HORIZONTAL_FACING (which all refer to the same value). The former includes all six Direction values, the latter only includes the four horizontal values.

This is a Vanilla bug that's fixed by Forge, see the discussion here. @fredvanYT Please keep this forum in English.

Use one of the static methods on the class to create a new instance.

You need to create a custom recipe type that overrides IRecipe#getRemainingItems to return a copy of the axe with its durability reduced. I've got a very similar recipe implementation here, there's code in other parts of the repository to handle things like registration and data generation.

Use the public BlockEntityType constructor.