While Google Translate has its obvious privacy-related issues, it’s at least a very mature system. The same cannot be said about Samsung’s translator, especially in its current form, yet they’re trying to roll it out ASAP and to as many people as possible.
So far, I’ve found it impossible to turn Google translate back on for quick access translations, instead I need to first copy the text, switch to the translator, then insert the text into the input field. This is more tedious than the previous method.
No, but does mean that Google now knows that you don’t speak Slovakian. It’s “just” the usual Google issues.
It can guess it, and will try to push for even translating languages you’re fluent in to your native one.