While it's possible that the single-nacelle vessel from Season 2 Episode 1 of SNW is intended to be *exactly* the same type as the USS Archer from S1E1, I was a little put off regarding how big it was next to the Enterprise when the Archer was (supposedly...) a small scout ship with a crew of three. Consequently, at least in my head-canon, I'm going to say it's a safe bet that the Archer and the S2E1 ship are indeed supposed to be the SNW version of the Hermes and Saladin classes respectively.