If want 10 satellites chasing each other around the earth (evenly spaced) all one the same plane, these satellites would be evenly distributed around the globe after launch by slightly raise or lower their orbits. As long as there is a few weeks available to do this, the adjustments are small so the deltaV required is minimal.
At first I asked "Does each satellite slightly raise or lower it's orbit to start spreading out compared to one reference satellite?" but comments suggest this has already been discussed in answers to Deploying multiple satellites from one second stage
However, if I want to do full global coverage and have this setup over multiple different orbital planes, would they each need a different launch? I assume the deltaV for a (satellite to make its own) plane change is too high to make it worth it?