This is a place to ask whether free open source software exists for a particular purpose. If it’s non-existent, specify your software requirements here so your dream can be well articulated for everyone to either laugh at or share the dream and give moral support for you to create it yourself. Or you might even to pitch the idea so well that a developer loves the idea enough to run off and build it for you.
No other community exists for this purpose but there are some loosely related ones. If existing software closely delivers what you need but is missing a feature, you might post a wishlist/feature request here or in !bugs@sopuli.xyz.
The FSF has a software directory that can help with finding software.
Loosely related decentralised communities generally for FOSS:
There is also foss@beehaw.org but I don’t recommend it because the mod is trigger happy with censorship. E.g. if you post about FOSS advocacy it will get removed as it does not relate to any particular FOSS application. There are also many more FOSS forums duplicated in centralised places which are not conducive to the digital rights spirit of free open source software, so they are omitted.