"The Hunt for Red October" had an interesting way of handling this with the Russian speakers. The movie starts with them speaking Russian with English subtitles, does a slow zoom into the Russian-speaker's lips, and switches to English mid-sentence.

With some elegance, too; iirc they pivot languages on the word "Golgotha" as he reads from the bible, the Latin word for a location near Jerusalem, but having a non-English/non-Russian word be when they switch made it a lot less jarring. Plus, having it be during a read-out-loud-from-book portion allowed for more measured cadence that smoothed the switch but probably would have felt jarring if the audience were parsing multi-character dialogue when it happened.

I found that incredibly clunky when I saw it. Also, it's a little bit extra jarring that Sean Connery goes from speaking Russian to speaking English with a Scottish accent.

That trick has been used in movies before that too. "Judgment at Nuremberg" does something similar. A character is speaking German, slow zoom, then a switch to English.