Riding my first ever TTT this evening.
I use my trainer for resistance and Assuomo Duo pedals for power readings.
The pedals have a 3-5s delay in transmitting the wattage to Zwift.
I imagine that this will have issues riding a TTT on Zwift with 5 teammates who are using smarttrainers for the power readings.
Is this latency issue going to cause problems with our cohesion? Any tips on how I can adjust my riding to this?
You have to anticipate the time for it to respond, back off early so you don’t overshoot the group, ride as steady as you can. I had a trainer that was similar (maybe not quite that bad) and with time and practice I learned how to modulate power pretty well to stay with a group and avoid accidentally getting on the front. In a TTT with everyone communicating and hopefully not making sudden surges it should be manageable but it depends on how well adapted you are to how it behaves.
Lead the group for whole event? 
Ha ha, there’s an ex pro in my team 
My condolences 
Are your pedals connected Ant+ or BT? Ant+ has in the past had issues with delays, both with my Trainer (H3) and pedals (Powertap P1). Switching to BT alleviated the delay.
Yeah with BT.
The delay issue makes TTT very hard.
You apply more power, your avatar doesn’t do anything for a few seconds, you add more power, then you fly too far forward…so you stop pedalling and fall back. Then you start pedalling again, but the 3 second delay means your avatar doesn’t move forward, so you add more gas, and fly too far forward again…
I rode 15k of a TTT basically alternating between Zone 1 and Zone 6.
Not recommended.