EQ doesn't work on the Android app?

My Roon Core is a Synology NAS.
If I play music from my Windows 10 PC, when I click on DSP I see many options, and they all work: Crossfeed, Parametric EQ, procedural EQ, etc. This is regardless of whether I set the PC itself or my Sonos speakers as endpoints.

When I use my Android app on my phone, instead, I only see CrossFeed, Parametric EQ and Audeze Presets. I don’t see Procedural EQ. But these options don’t work: I can click enable, but there is no “right arrow”, like on the PC, to access a screen with the relevant options. Clicking on them does nothing. The same applies if I set the phone or the Sonos speakers as endpoints.

Is it a known bug/limitation?

Short answer: Yes

Longer answer: You need the landscape UI, either on a supported tablet (see below) or on a PC/Mac, to setup the DSP options. You can even configure different presets for a zone there. With the portrait UI on a phone you can only enable/disable DSP modules or change presets.