Yes, I can confirm that sfradel’s solution works really well! Thank you!
Naturally, if you enter multiple languages in Yoast fields that are limited by number of characters, you will get some warnings. But just ignore them. The limits are not applied when you save the data, so the full strings will be in the source code anyway (as long as each language stays under the limit)
Example usage:
Meta Description:
<!--:en-->Cross-platform mobile apps and IT consulting. Mobility solutions.<!--:--><!--:sv-->Mobilappar och IT-konsult. Mobila l?sningar. kdfjhskdfjhksfhskfjhskjfhksjfhdsfsdfssdffdssdj 1234567890<!--:-->
You get the following warning in the SEO admin:
The meta description will be limited to 156 chars, -11 chars left.
However, the full text strings are printed on the web site in each language.