Pixiv commentary auto-translating? Or has alts now?

While uploading post #9896243, I noticed that the commentary had changed from English on Pixiv, to Japanese in Danbooru's commentary field.

If anyone has similar cases from Pixiv uploads, please share. I have yet to discern if this is automatic translation, or alternate commentary provided exclusive to whatever language is selected for the Pixiv user.

What is known:

• Setting your language to Japanese will display the Japanese commentary
• Setting your language to English will display the English commentary
• Setting your language to anything else will display the Japanese commentary.

Alternatively, a relevant changelog from Pixiv would be appreciated.

I've seen it a lot for a long while now, it's usually specific artists that has it so it's most likely a toggle. I know Iroha (Iroha Matsurika) has it, but it's the only artist I can think of right now.