The phase issue on ns1000m exist in the bass/ mid section of the crossover, there's a phase shift relative to frequency.
If its the same on both speakers, ie well matched drivers and crossovers, it'll have no issue on Imaging as that's a product of polar response and frequency/power response.
What does affect Imaging is the big bluff square cornered cabinets. No way around that apart from running them close to the back was, as intended.