I’m currently using the Flame µQMCV which gives you 4 channels of gate/pitch/velocity plus reset/clock and one extra mod and pitch wheel output in 5hp. I also grabbed the µ16MCC to add additional CC outputs. These have MIDI thru but I have experienced some odd behavior with it. (if I’m sending clock to one, the second one’s learn mode gets stuck on)
Others I’ve used:
Expert Sleepers FH-2 - enough said about this one, it’s great. Lots of options and you can change the behavior right from the front panel in a pinch, which is nice. Plus any output can be anything including bi-polar. And it’s got a ton of bonuses like euclidean sequencers, etc.
One really important feature FH-2 has is the ability to convert gates to triggers or envelopes. The envelope stages can be controlled by CC, but not via the front panel. But if you have a CC enabled sequencer this can be super useful.
Michigan Synth Works mBrane - a 6hp version of Mutable Instruments Yarns. Again, configurable via the front panel which is handy, flexible output arrangements, good value for size/money/etc. Plus it has a MIDI thru which makes for easy expansion.
Polyend Poly 2 - Tons of outputs and fairly easy to configure, just beware it’s just been discontinued and the clock output goes wonky when making config changes. This isn’t a deal breaker for most since generally you’re not going to change your MIDI to CV routing in a performance but worth knowing.
Squarp Hermod This is a sequencer, but works great as a MIDI to CV interface. It takes up a lot of room, but adds Squarp’s MIDI FX which are a lot of fun in a modular environment. This includes things like arpeggios, scales/quantizers, LFOs, euclidean sequencing, etc.
ALM mmmMIDI Great value / size and dead easy to use. But no way to add more CV outs, just triggers. If your needs are basic this one is great.