Is it possible for PKHeX to modify which Starter I chose?

[Dio_Vento]

I'm working on a romhack, and I'd love to be able to tweak the save I have right before Brendan/May to see if all the teams are working properly.

[Kaphotics]

The Event Constants store 16bit numbers per entry (as opposed to Event Flags which store only 1bit per entry).

Event Constants keep track of which starter you have chosen, and many other things the game has to keep track of that isn't as simple as a true/false.

Like most flags, those are un-researched. You can access a dropdown preview list in the Event Flag Editor.

Based off of my experience with scripting in the DS games, you'd likely see a 0/1/2 stored as an Event Constant as that is what the game uses to switch between the 3 possible starter battles ~ (it has another switch earlier to select Brendan or May).

[Dio_Vento]

Ah, so we don't yet know which address is the starter choice? Thanks for the info!