I’ve been doing this for a while.  I have the H9000 wired into a Sound Sculpture Switchblade GL.  I then can put any of the EFX engines in front or behind an AMP in 4CM.  I then have the optical looped back to itself on the H9000 in case I want two FX Chains in either position.  There is almost no latency and this is with the amps in a tracking room and being heard back thru studio monitors with a bunch more AD conversion.  Yes it is there, but you should be able to handle it.  Any buffer sensitive stuff is right after the guitar in a relay switcher.  The tone is effected, but it just means you have to dial things to get what you want.  Don’t go into this stuff thinking that you can dial amps the same as when you are connected right to it.

As an added bonus the same H9000 is wired into the studio via DANTE card and by simply changing sessions I can use it in studio mix mode without touching a cable.  It’s an amazing machine.

Sounds like you are having fun too!