I was able to load 21 DLC for Gal*Gun 2 with crash. Might be because I used devmenu. You might've installed a corrupted DLC. Delete the software and try installing the DLC again. Make sure it's for the game's region. US & JP both have a different title ID
Yeah I had trouble with the
downloads at first, but I did fresh
downloads for each dlc. A corrupt one was my first thought but when testing to find the corrupt dlc that is when I realised all dlc will work without corruption, just so long as I don't install more than 8.
I use the US dlc, on an eshop dump of the game (which is the same version for EU/US), sitting at 5.1 exfat. Oh and I have the latest update installed too.
I'm not sure about using devmenu, would need to get hold of it somehow first, but I've heard it can mess up the switch just by having the nsp installed unlike the 3ds devmenu.