Nice! Can you give me your save?
This *should* be compatible with all regions, I only own USA, as you can obviously tell, but past me was smart enough to save the file I dumped with TCPGecko forever ago. I'm not sure if it moved in memory in 2.6.0 but on 2.5.0 it's at 0x12CCDA00, 0xD000 long (even though the FS allows for a max of 0x10000). Should have all weapons and gear, people in the plaza from online, you can edit 0x180 in the save to change gear if you know the ID (open up the BYAMLs using some tool like yamlconv).
According to notes, it's Clothes, Shoes, Head, Weapon, ModelID (for Octolings and M/F), skin color, eye color, and the sections below are Shoes, then Clothes, then Head, then Weapons which have a smaller entry size (0x28 instead of 0x30).
Gear entries are ID, slots with an unlocked abilty, slots visible, ability ABC, and that 0x00010000 is whether it shows *NEW* in Equip.
Weapons are ID, some hash/sorting number, sub and special (doesn't actually do anything, have to edit the BYAML that pairs them with the weapon in Static), turf inked, 8 0x00's, some hash, then the 0x00010000 for if it's new or not.
Your stats are at 0xA5A0, Money, Experience, Level (minus 1, 0 is 1, up to 0x31 is 50 IIRC), Rank, Rank Number (EG 0-99), and then number of Super Sea Snails
At 0xB100 they cache some statistics that gets uploaded to splatoon.nintendo.net AFAIK
Starting around 0xB400 is the Plaza data, no idea the format, never bothered.