Playing MHGU via an emulator offers several massive upgrades over the original Nintendo Switch hardware:

If you're looking to download a ROM of the game, I must remind you that:

When searching for an MHGU ROM, you will primarily encounter two file formats designed for Nintendo Switch emulation:

Emulators themselves are entirely legal to download and use. However, downloading copyrighted game files (ROMs, ISOs, or XCI/NSP files for the Switch) from third-party websites violates copyright law in most jurisdictions, even if you already own a physical copy of the game. The legally approved method to play MHGU on an emulator is to use a hacked Nintendo Switch console to dump your legally purchased game cartridge or digital eShop download into an NSP or XCI file. Risks of Third-Party Download Sites

Instructions on how to to the Switch version? The best Armor Skills for early G-Rank?

These are essentially "cartridge dumps." They are often preferred by users who use custom firmware on an actual Nintendo Switch.