Hyades Sector BV-O b6-3 and 5 Mu Leporis seem to be getting dragged along with the Matrix systems as well.
This effect doesn't require Matrix systems to be in the exterior range - the three inhabited outer Controls at Oya are moving in step, for example.
Whether the effect strength depends on how many systems are in the periphery zone is definitely an open question - I'd suspect not, given the pre-U17 behaviour was to apply the same effect to all counterstrike systems regardless of how many there were at each Maelstrom - and in that case, the only reason to directly act on a periphery system would be to push it over the line - but should be relatively straightforward to test in theory by doing the same action at a couple of the quieter ones with different numbers of periphery systems.
This effect doesn't require Matrix systems to be in the exterior range - the three inhabited outer Controls at Oya are moving in step, for example.
Whether the effect strength depends on how many systems are in the periphery zone is definitely an open question - I'd suspect not, given the pre-U17 behaviour was to apply the same effect to all counterstrike systems regardless of how many there were at each Maelstrom - and in that case, the only reason to directly act on a periphery system would be to push it over the line - but should be relatively straightforward to test in theory by doing the same action at a couple of the quieter ones with different numbers of periphery systems.