Can’t get Double Dash LAN to work

I’ve been trying to set up lan play for double dash to play with my friends. I just can’t get the HLE bba to work. Everything online seems to state that my two PCs on the same internet should just connect. But I can’t get them to see each other. I’m using the exact same copy of double dash for both PCs and the same version of Dolphin. I’ve honestly spent hours looking up different things to try and do this and I can’t find anything. Tons of really old outdated posts, half solutions, videos that don’t actually show the setup process. I’m stuck, and any help would be appreciated.