In Spain, the word for a fish burger is “pescado hamburguesa.” In Mexico, it’s known as “pescado frito.” This is a difficult question because there are so many language differences. For example, in Spanish, the word for “fish” is “pescado,” but in English it’s spelled differently.
The phrase “un hamburger de pescado” means “a fish burger”, and it’s an expression that can be translated into English as “fishburger”.