Possible to limit internal traffic speeds between clients?

[Frosty81]

I am trying to limit the bandwidth between two machines. They are on physically separate networks that are connected over a site to site wire guard tunnel. So far I have not been able to get speed limits to work. I noticed during testing that a speed limit worked on my pc when my pc was communicating with the internet, but if I copied files too/from my pc to other destinations on the network, they would transfer at full line speeds. So this leads me to believe you cannot limit speeds between 2 devices on a "local" network, but I wanted to double check with the pro's to see if that's the case, or it this just takes some special tweaking to get it to work.