I can now confirm that my half-broken range extender is considered the same network, and the streaming works.
I still bought a new mesh extender as a back-up, but this is perfect for what I need.
I've hacked 3DSes before, but they were the "old" models, so I'm not familiar with the capabilities of this.
Due to how my house is set up, my PC is on a 20m LAN cable to the router, with a range extender for my phone and 3DS. I got a Pokéball New 2DSXL in the post today and I want to use this...
leo @'d me in a thread about his last dream, stating he was passionately making out with a guy he used to know and then woke up while reaching for his crotch, and said that i would "know who 'tf' it is"
and of course i know, it's luke