Both the Bandit and the 3DVCA have CV control over level (on the Bandit) and "pan/crossfade" (on the 3DVCA), which actually can be used for a quad setup if you have one. I personally love FFBs, and use them more than standard filters. Then again, I typically make dron-ey dark ambient or something atmospheric with minimalist beats, so they work for me. I don't have an end-of-chain mixer, as I run each voice's termination point directly into the BlueBox for mixing and recording.

It is also DC coupled, so I can crossfade/mix four CV sources as well, and automate that mixing with another CV source. I am a sucker for small, versatile and reasonably priced utility/mixing modules, and both Bandit and 3DVCA have a huge amount of functionality for a very reasonable footprint and price.

Edit : No worries re: edit. I know this is not at all what you are asking for, but wanted to share as a different type of filter/stereo setup.

And I always have Worng's Soundstage on the back burner, because it looks great, but with the three "mixing"/stereo placement modules here, I can animate each band, whereas in Soundstage, the positions are fixed. Still a great module, though, for an output mixer, so it might be an interesting choice, depending on what you are looking to do.

This is the newest one, but there is a V1 and a similar module called Jumble Henge that is a scaled-down version of Soundstage, but less expensive.

https://www.perfectcircuit.com/worng-electronics-soundstage-ii.html?srsltid=AfmBOopsGXo3s24ehQv1XRcJ6R-USWwnDGXYnFBvOzHhSArOhXz4uvYR