Change menu's words and content according to user's language (without polylang)

I’m using gt3’s Pure theme and it only supports one menu.

Thing is, I need a multilingual site and figured that simply having an option to change the menu’s content and words according to the user’s language would be easier than applying a Multisite feature or using a plugin such as Polylang (I tested it and it conflicted with some of my pages as well, so I’d rather not use it again)

And this doesn’t need to be about languages at all. It is simply a matter of the user picking an option in the menu (in my case, the language), and seeing its content change for the rest of their navigation. Example:

Menu 1: portfolio | about | Contact | Português

The person clicks in Português, and the menu changes to:

Menu 2: Portfolio | Sobre | Contato | English

And stays this way even if they visit another page.

Is there a way to set this up using a simpler plugin or the editor?