SEO question
 

Hello guys,

Maybe someone can help me.
I have a website in two versions, french and portuguese language, in two different domains.

They use same theme/layout and same content (except language)
Isn't Google punish me by duplicate content?

Or should I use any tag? Like rel="canonical" or rel="alternate" ?

Can someone help me? :)

If you setup your sites in GWMT as having different languages you will be fine.
Rel canonical have other meaning (same page having different url's), but as you said, your pages have different texts (different languages)

Thank you for your reply buddy.

This is the websites:

FR: Le Meilleur du Porno
PT: Sites Porno

How do I setup my sites in GWMT to different languages?

Go to your Search Console on Google Webmaster Tools, then on the sidebar menu go to Search Traffic > International Targeting.

Why did you choose to use different domains? Why not a sub-level for each language?

This can be easily done with Wordpress and a plugin like qtranslate or similar.