Has anyone ever managed to manually edit game saves?

Basically what the title says - since there is no save editor for ER, and the debug version doesn't support ability/innate changes (at least yet), I am trying to figure out how to edit a save manually using HxD (hex editing).

So far, I have had no luck - ER seems to use a vastly different save structure than vanilla Emerald, and I have tried converting Pokemon/Ability numbers (from the ER Nextdex) into hex format and searching for them, but either not finding any results, or finding WAY too many of the same.

If anyone has had luck achieving this, or has any pointers, I'd be most grateful. Thanks in advance!