Translate shortcode

Hello,

I have a few string I can’t translate, like theme strings. Is there a way to have that kind of shortcode:
[polylangtr lang="en"]english text[/polylangtr][polylangtr lang="fr"]french text[/polylangtr]

The only post I found about that is this one:
https://wordpress.org/support/topic/polylang-shortcode-like-qtranslate-for-theme-options-and-text
But the solution doesn’t work for me as I get a white website when I use the function add_shortcode.

Thanks in advance,

Regards,

Cédric

https://wordpress.org/plugins/polylang/