In my experience it works ok. The "English" model actually knows a lot of languages and will translate directly to English.

You can also transcribe it to Japanese and use a translator to convert to English. This can sometimes help for more semantically complex dialogue.

For example, using faster-whisper-xxl [1]:

Direct translation:

    faster-whisper-xxl.exe --language English --model large-v2 --ff_vocal_extract mdx_kim2 --vad_method pyannote_v3 --standard <input>

Use Japanese, then translate:

    faster-whisper-xxl.exe --language Japanese --task translate --model large-v2 --ff_vocal_extract mdx_kim2 --vad_method pyannote_v3 --standard <input>

1. https://github.com/Purfview/whisper-standalone-win