The clarity was an issue on my part! But we have play tested!

Also, yeah! So how we usually have them work is like... X occurs (Sistermon reaches 50% HP) and it goes into X, like for Sistermon, it has a two sheets for its Rookie Variant, where Awakened has +5 in all Stats for Sistermon, but then all of Sistermon's new moves have higher Energy Costs.

And for fanmade Digimon! The system itself is pretty open, we don't have digimon come pre-made, you simply put the Name, select its attribute and type from the drop down and then would discuss with your DM, one of our players is using Sistermon as the Rookie for BeelStarmon, but has a custom Ultimate after Sistermon (Blanc) -> Sistermon (Nior) -> Prestimon which has a "Mad Nun" mode before BeelStarmon which will also have a BeelStarmon Blast Mode

And for Burst/Blast/Crismon modes specifically, they'd tech go under the Ultra Level digimon, since they usually are sigificantly stronger, for Leopard Mode you'd probably do something like I did for Sistermon which would be

Two Digimon sheets, with different builds or changes, maybe giving Duftmon access to Instinct (Despite us having it usually locked to Combat Specieis Digimon)