Hi Lluis,
I copied the helix ultimate template and named them
shaper_helixultimate-EN
shaper_helixultimate-NL
In Details - Template Options:
Menu: Main Menu (en-GB)
Menu: Main Menu (nl-NL)
https://edzedeboer.nl/joomlang/en/
The only thing that I changed is:
In Menu Assignment for each template:
Toggle Selection Main Menu (en-GB), items Home EN and Contact EN
Toggle Selection Main Menu (nl-NL), items Home NL and Contact NL
I linked the Menu-items to the SPPB Pages.
Everything is working fine.
Kind regards, Edze de Boer