Yes this is caused by Dual Arms, I wish it wasn't the case because I always play with it, but remove that from your load order, it may tell you it's required, but it's fake news.

Hi slay thanks for the amazing mod! Just one problem, me and my friend are trying to play together and his game keeps getting stuck at the loading screen. Once I'm in I can see him move around and he can clearly hear when I am walking and running past him. But his game is still stuck on the loading screen. Any help would be awesome. Thanks again!