Arzad is the only current Amarr system we have a definite on being originally Minmatar.
Beyond that, other PF-named systems include
- Ennur (Molden Heath, sight of a clash by Minmatar/Amarr fleets)
- Audesder (Molden Heath, originally Nefantar-owned, believed impossible for the rebellion to retake but one of the last systems captured by the fledgling Republic)
- Hjoramold (Molden Heath, site of Rebellion-era Nefantar government, "neighboring constellations" had been Nefantar/Amarr at one point as well)
It seems likely that large portions of modern Molden Heath and Metropolis were at one point controlled by the Empire and/or Nefantar forces. It's worth noting that Hjoramold is nowhere near the nearest (in terms of jumps) link between Metropolis and Molden Heath (and thus, quite far away from the current Mandate border as well).