Ableton Link - what can it control

I bought Pulse to send out Ableton Link BPM data. Works great in Resolume. But now I want to sync up Onyx. Got link going. But I can figure out what I can control with LINK. Doesn’t seem like I can control the FX engine at all with it. I see it in dylos but haven’t got it to control anything yet. What’s the purpose of link as of 4.9 RC? Will it control the FX engine? Is there a updated manual or YouTube video anyone can point me to with link controlling anything in Onyx?