Logic plugins not provide sidechain input option

Many of my plugins contain the sidechain button but do not provide the drop down menu where I can select the input for the sidechain. This is the case both for third-party plugins and also for some of the native plugs (for instance, the Expander, which I've screenshotted).

I'm on a Macbook Pro running Sonoma 14.7.1 and my Logic version is 11.2.2. I have tried deleting the app and reinstalling, and I've tried resetting my audio units, but neither solution has worked. Any ideas on how I can get my plugins to sidechain properly?