I'm probably over estimating my own popularity, but I created a discord server to chat with people from the different sites I'm on. There are channels for general fandom categories like TV, Anime, and Books. There's a channel for posting your own discord's link, and I have a few for some of my writing projects, just in case.
I can put people in groups, depending on what site they've come from too; and there are channels dedicated to each site (dA, Wattpad, Fanfiction, and SmackJeeves). You can post once a day with a link to your related account in these channels, though they are mostly for talking about stuff related to what goes on the site