When you walk with Coros and cadence is below 130 SPM, the watch will use wrist motion and GPS to determine pace, distance, power, and other metrics. This is because Stryd will currently go to stand-by when paired with Coros and you are not running. The Coros development team is working to address this limitation.
When you walk with Coros and Stryd, the data may or may not transfer to PowerCenter.
Interval Workouts with Walking Recoveries
The above refers to cases where the entire activity is at a walking cadence. For workouts where you alternate between running intervals and walking recoveries, here is what to expect.
Stryd will switch into Run mode after approximately 60 seconds at a running cadence (>130 SPM). IT will stay in Run mode as long as this threshold is exceeded, and remain in Run mode for approximately four minutes after dropping below the 130 SPM threshold. This means that as long as the walking recovery is less than four minutes long (before returning to a running cadence), all power data to your COROS watch will come from Stryd.