(I've got permission to post this, ask Moegreche.)
Here is the mod page with the link and the details (Sonny Wiki).
-Rebalanced abilities, leveling, classes, items, teammates, enemies.
-New abilities, enemies, stages, items, builds, allies, training fights, strategies, and a new 'area of effect' ability.
-More accurate descriptions/info.
-Fixes, bonuses, extras, references, secrets.
Version 1.4 (2022 February):
-1 new default ability for each class.
-Set training enemies to always be 2 levels below Sonny (except zone 6).
-Changed item tooltip.
-Minor design and balance changes.