Fortnite on Nintendo Switch Hotspot?

I'm on vacation and would like to play fortnite on my switch and wanted to know when I connect it to the mobile phone hotspot how much MB it consumes per hour or so

You can only guess that… But I would not recommend it to you. It's an online multiplayer game, so upload your data to Runzerlad and in the same moment. Once you get bad internet, you'll probably get kicked out of the game…