You can have non-curseforge mods in a modpack as long as you give appropriate credit, and the mod's license allows it. For example, my modpack has Galacticraft, because I link to it on the mod page. However, I couldn't add OptiFine because of licensing issues. Hope this helps.
Also, this forum is pretty dead, you should ask in a discord server or something.
Twitch Vs Minecraft (aka Streamer Vs Chat) lets your Twitch viewers interact with your game while you play, by typing commands in chat.
This is a mod I've been working on since June, and I really want to get more streamers to try it out. Interactive streaming has finally come to Minecraft. The mod is currently available on CurseForge for Minecraft 1.12.2.