So, where does wearable resistance (WR) fit in the periodised plan? This is a FAQ. Short answer, anywhere. You can combine WR (combination training) with your general/maximal strength training which tends to be high force-low velocity training. This means you can overload high velocity, more specific movements in the general strength phase if you so wish.
As velocity and specificity needs increase such as in the speed-strength/ power phase, then WR can be used as a stand-alone training tool or can be used in conjunction with gym-based strength-speed type training.
If you are requiring special strength specific to your sport, then WR should be the tool you consider seriously, especially if you sport requires high velocity, multi-planar motion. It has the added advantage for the time poor and those sports with congested schedules, as your strength training can become part of your on-field training e.g., as part of a warm-up or small sided games.