There’s Host a Sister on FB and an automated group on Russian VK (the admin of which suggested this idea), and I’d guess there should be some others as well.
So, maybe it could be somehow possible to integrate them, like if a person states that they can host people, they are offered to be shown on Couchers map as well with the data they provided. And if someone sends them a message/request, they get it on the social net they use. The group would probably need to adjust the format of their host descriptions to match the info Couchers require, but for example the VK one is all in for it.
The thought behind it is that any hospex website first of all needs hosts, and that could be a way to make joining the platform much easier for them.
I feel this can be complicated safety-wise among other things, but maybe we could get something out of this idea?