Different cars with different setup will respond differently. Duh!
But for what it's worth I ran both ways quite a bit. My best setup for square was middle adj hole on the front sway and softest rear sway setting. When running staggered I liked full soft/soft running NT-01s. Tires with more lateral grip might need more (firmer) sway settings but try this as a starting point.
I did a lot of testing over 3 years and nearly always ran faster staggered but only by a few 10ths. AX was faster square hands down. In racing, a good square setup might benefit heavy braking, passing into corners and holding your line in heavy traffic. Data showed I nearly always gave up some top speed at the end of a long straight.
Everything is a tradeoff.
Don't underestimate the fact that you have been out of the saddle for a while and the edge is dulled a bit. Back when racing MX/Grand Prix I found that sitting out for 6 months due to injury required 1-2 months of weekly racing to get my competitive edge back. My first few days back in expert class usually resulted in a DFL finish.