Wondering if there are any filter plugins that offer sidechain inputs for their parameters. For instance like if I could chain the filter cutoff to a send from a delay track so that the cutoff would open as the delay received signal and then would slowly close as the delayed track goes silent. I wouldn't know what options are out there because i tend to stick to sonitus. What do you recommend?

FabFilters Volcano does

Meldaproduction's MDynamicEQ and MAutoDynamicEQ do, too.

Thanks for the input! (pun intended) I'll check these out, was going to ask about eq next