Hello! I'm Jen, and I'd be happy to help you out with this issue.
I'm sorry to hear you're experiencing this issue. As a fellow player, what has worked for me in the past whenever I encounter crashing issues in the game is disabling high resolution textures. Kindly check if you have High Resolution Textures enabled as well. If yes, then try turning this off and see if it resolves the issue. Close the game first, then open the Epic Games launcher > click on Library > Right click on Fortnite and select Options > Uncheck 'High Resolution Textures'. Also, ensure that 'Pre-download Streamed Assets' is checked. Click Apply and then restart the game.
Let me know if this solution works for you. If not, please feel free to reply, and I'll be happy to provide further assistance. Thank you.
Best Regards!
Jen :)