Hi -
There is a rather long forum thread on PowerMatch experiences which may help with your particular problem:
For myself, I have a 2017? Kickr snap (version 3) and I use a left side Stages Power meter with TrainerRoad. After experimenting with PowerMatch for a while, I have turned it off as I find the feedback loop too long. In other words, in ERG mode, it takes too long for the trainer to apply resistance to match the target. With PowerMatch, it always feels like I am chasing the power target, leading to a poor user experience.
Instead, I have much better success with turning on the “Control with Ant+ Power Meter” in the Wahoo Fitness app and having the Kickr use the power reading from the power meter. In the TR app, I disable the PowerMatch mode and only pair the PowerMeter for the cadence reading. With this setup, the trainer in much more responsive in ERG mode to power target changes, even with short high-effort intervals.
In a recent YouTube video, Shane Miller highlighted that there is still too much friction/effort on part of the users in getting the various technologies to work nicely together. I probably have seen at least half of dozen posts on TR’s facebook page and forum with issues in getting power meters, trainers and training apps to provide a simple and problem free user experience. Good luck, hopefully with some experimentation and maybe customer support you can get it figured out!