Kaphotics

None of the above. Install custom firmware, then dump your save files with homebrew apps like JKSV or Checkpoint.

Pretty sure I've said this in multiple places, but you need to update both the CurrentAppearance and CurrentFashion to match what the values should be when changing anything about the player's visual identity.

Doubtful; the RNG seed does not yield the PID/IV that you have on the file, indicating that something was modified (such as the Encryption Constant).

Attached file is not a save file, it is a Legends: Arceus block dump from PKHeX's Block Data editor. You likely overwrote the wrong file. Restore a backup.

Should be fixed on the latest release.

Transfer your save file correctly. It is not a valid save file (I have hidden your attachment of your save file). Assuming you used an FTP application to transfer it, be sure to turn on the Binary data type transfer setting (not ascii/text). Data Type - FileZilla Wiki If your save file is slightly too small, it should imply that it was truncated. This is not a PKHeX problem.

Did you originally open the zip file from a file/folder that you later removed from your computer?

Try saving again in-game in a separate play session. That way both halves of the save data are populated correctly. Web editors using PKHeX are the same backend code.

PKHeX works properly. As I already said, you need to change the values for current model appearance. PKHeX already lets you change PlayerAppearance and PlayerFashion via the Block Data editor. The save editor script you mentioned uses leaked source code/information (not legal) in its implementation, and I refuse to read/reference it. Changing the player's appearance/fashion automatically when gender is changed requires someone to dump the default fashion/appearance and implement it in a pull request. It is not worth my time as other featurese are much more important, and such a feature primarily is only useful for players who are using other people's save files (more frequent in pirated game copies).

As I already said in this thread: You should be using the name, not the index within the list.

DLC has only been out for a couple of days, and you expect PKHeX to be updated with various quality of life edits? Temper you expectations.

Use the Block Data editor to change the Starter choice.

Oh no, the game doesn't like my level 5 alpha legendary! Start with a legitimate copy, then see what you can get away with changing. Gross hacks are gross.

Changing Gender Causes Infinite Load (Legends Z-A) · Issue #4614 · kwsch/PKHeX

Outdated version of Wine. If you googled the error message (DpiAwareness) you'd find discussion from over a year ago.