Hi Chouby,
thanks for reply.
I'm not a theme developer, for a client I've buy Studiofolio, very fine theme but developers did not provide i18n support for the internalisation.
With several changes to the code I was able to add the second menu and make it multilingual site.
As wrote, I've translated many strings of the wp theme using pll__ or pll_e in php files, but not being able to translate button text and button html text that using javascript function, any suggestions?