It depends on how you got access to the game.So i know you need the latest patched mhxx but when nintendo updates it it says it in the downloads but it never updates the actual game it just says this game needs an update. is there a way around this?
If you pirated MHXX on a CFW 3DS, then you will need to find a .cia file of the update and install it with FBI or whatever you use. You must find this yourself and we cant help you here.
If you are playing an physical version with a USA/EUR 3ds and Homebrew, then I am afraid you can not access the patch. The best thing to do from here get CFW on your 3ds, dump the game and install it and then find the update file and install that as well.
If you have a Japanese 3ds or have changed your 3DS's region to gain access to the Japanese E-shop then you can download and install the patch from there.