Is there a possibility of translation into other languages in the future? Or will it always be only Spanish and English?
First, im not a devs spokesman, those are only mine opinions.
More language choice - more player base, more potential patreons, BUT only if they play original download, even for free.
I guess, it also require swapping language files, it may be difficult for most players, especially on phones, and downloading game with altered files from other sources is very risky and not in favor for devs.
So, like the best option is some1 makes a translation and send it to dev for implementation.