For those of you wanting a 'new update'; there haven't been any significant changes to warrant the release of one. No new features (in terms of editing, not usage) have been identified, primarily because PKHeX already does so much. I'd much rather use my time for other tools (relative to 3DS ROM editing, which is possible).
The game language can be set to any language, but the CARTRIDGE itself (manufactured region) matters.
Cyber Save Editor only supports Japanese cartridges (the company's decision); PKHeX supports editing of their decrypted save files, of which they accept and encrypt for you... so long as you're using a Japanese cartridge.
PKHeX edits essentially everything in the save file, including Pokemon.