Amethyst on my android but translations suck ass
Also have damus on iphone for the Japanese with purple auto translation which suck a bit less 

 rabbit has real-time free translations https://i.nostr.build/tC5f1p8Lj4FyvqDZ.jpg  

 Huh where do you enable this?
 

 Click the + sign to add a new tab choose the Japanese tab 


I also always click Japanese -> English when I start the page n get the pop up 

 Yeah I have the tab.
Ok it's done by google translate then.
Seems to be quite good
 

 If you’re on chrome that is (i think)