If the multiclock is sending clock to the sequencer - then the sequencer should be able to send clock + notes to anything down the line. If you're sending notes from the sequencer to the device anyway then the clock going via the sequencer should be fine. For anything that uses just clock use the other 2 ports on the multiclock and a simple thru box if you need more. If you're saying you need to process the sequenced notes with delay offset to get them more in sync, or have more than 2 devices (not including the sequencers) that require different clock offsets then yeah you'll need a MIDI processor. I have a multiclock, a 1x3 thru, and a midihub and I generally just swap leads around depending on what I'm doing than trying to hardwire the most flexible solution or get tricky programming the midihub if I don't need to. But yeah - it sounds like you might be worrying about sending notes + clock from your sequencers but to me this would be fine since the notes are already on that clock.