How to move apps to sd card that can't be moved normally... on an NEC Terrain

This sounds simple, but terminal commands don't work (there aren't any drivers that let me access the device from a pc without a root, and using a terminal app on the device, the command to change the default storage always results in a "killed" error), and there isn't any way to get permanent root access (for the NEC Terrain in particular) that would allow me to move apps to the sd card manually. To be clear, I'm trying to move apps that have the "move to sd card" option greyed out in the settings menu, that aren't critical to the operation of the phone (I'm not trying to move the Google Play store, for instance).

If Move to SD card is grayed out, it's because the developer knows that the app won't run from the card. You can move all the files of the app to the card if the phone is rooted, but it still won't run. (Widgets, for example, won't run from the card. Neither will any app written using a library [or class] that won't.)

The only "solution" is to buy a phone with enough internal storage. (Even adoptable, or internal, storage isn't the full answer, because now you have no control - Android puts files wherever it wants to, and you can still run out of space when there's seemingly loads of free space left.)

Thanks. I've read about other people who moved apps from the main storage to their sd card without any complaint, but I always assumed that the apps still worked when you moved them (I knew that this was a problem with blackberries, but not android). Also, the apps that I want to move are like google chrome, which shouldn't have trouble moving to an sd card if firefox and instagram can. If I can't move any apps to the sd card and have them work, it would be nice to at least free up space by removing the apps that come preinstalled that I don't use, because the "su" command that lets you delete those apps from a terminal doesn't work on this phone. (I'm the thread creator, and it had me create an account in order to reply, thus the different username)