Seems like this would be better served with just patreon and only fans integration. Discord could charge the creators to turn it on. Why would I subscribe to someone once on there and then again to them on discord.
It depends what the "primary" place is. If poeple go to Patreon to receive a product, and Discord is a sidebar to that, then yeah, keep it to Patreon. If a Discord community is funded with a Patreon, this can be a replacement.