Change keyboard on external keyboard

I'm using latest version of SwiftKey and Android on Samsung Galaxy S10.

If I use SwiftKey using external physical keyboard such as Logitech K850,

I know that Ctrl + Shift changes the language between English and another language such as Spanish.

If I want to switch to another keyboard app such as Samsung keyboard or Google GBoard using only physical keyboard, what should I do?

(I know touching the 'dots' on the lower-right corner does that, but I wonder if I can do this using only physical keyboard)