can I just switch my modded switch to primary console for now to install this?
if it's not banned, then you can go on the eshop on the other one and remove it as a primary console, then go to the eshop on the modded one to make it primary
it's probably easier to just download nsps online and reinstall the games you need though, you won't lose save data because it's stored separately so you dont have to worry about that. but if you wanted to keep and use what is already installed then just installing a ticket should work
well, I say that, but there could be additional encryption on the contents for personalized eshop content and that could apply to games downloaded from the eshop on a secondary console, and then simply installing a common ticket with the common title key wouldn't be enough. it might be interesting if you actually tried and reported back to know if simply installing a ticket actually works
or actually it's probably easy to verify this, just dump a personalized nsp with nx dump tool and then dump the same game but with the console-unique info removed. and then compare if the nca are identical or not. I can probably do that at some point, and then I could test if the personalized nsp install still works if you just install a common ticket over it
or at least, nx dump tool doesnt seem to do anything to modify the contents when you dump a nsp with the console-unique data removed, it only modifies the ticket to make it a common ticket
https://github.com/DarkMatterCore/nxdumptool/blob/rewrite/code_templates/nxdt_rw_poc.c#L6883
https://github.com/DarkMatterCore/nxdumptool/blob/rewrite/source/core/tik.c#L193
so it sounds like in theory a fake ticket should work just fine with the legit eshop contents
there might still be a problem though, because there could be an entry in the title database with rights id associated with that title, and if you dont have a personalized ticket with matching rights id, it might not accept the ticket and the game still won't work. thinking about it I think I've already tried that in the past actually, installing a common ticket over a personalized ticket, and it didn't work. but I don't know if game installs on secondary console also do that, or if they just connect online to get the title key
it would probably make sense for it to also check the license to make sure the game is actually owned in which case simply installing a common ticket will not work and you should forget what I said in my previous posts, your only option is likely to uninstall the game and reinstall from an nsp. if you dont want to have to download a pirated nsp online then you might be able to install a fake ticket (with the correct title id and title key of course), dump the game as an nsp using nx dump tool or dbi or anything you want, uninstalling the game to clear it from your switch's title database, and then reinstalling it with any nsp installer (which should install it properly as a non-personalized title, and should work fine with just the fake ticket)
your easiest and most straightforward option is to download an nsp online and install it though. you own the game legally already anyway, so if you werent a fan of piracy, this should at least be okay morally. or if you can access the eshop on the modded console to make it a primary console, that should work too (and I'm pretty sure it will just download and install the personalized ticket once you go to the eshop)