You’ll need to buy either Queen Dizzy, herself, or the Season 4 pass, to be able to play her in Strive. She is $7, by herself, and the full season pass is $25 (which will also add Venom, Unika, and ...
The team at Arc System Works acknowledged the latest patch's issues and promised to prioritize another update.
Prime 1 Studios is currently working on new 1/4 scale figures of Dizzy and Ramlethal Valentine from Guilty Gear.