MyNetwork is essentially a brand for an independent station with some syndicated repeats in prime time. Sinclair has mostly kept the branding intact, aside from WPNT (22 The Point) in Pittsburgh. They serve as duopoly partners to their primary stations in markets such as Pensacola, Asheville, and with the Allbritton merger, serve as the host station in Birmingham (hosting a full powered feed of 33/40) and Charleston (WMMP becoming the new WCIV, with the old "WCIV" on the .2)
Other places like Norfolk, it's just a standalone station that bet against Fox years ago, and is a subchannel in others like Columbus, Chattanooga, and have taken over the primary stick of WRGT after the former "Fox 45" moved to WKEF.
While some have a strong lineup in their own right, many are just pass-through operations for ThisTV or other networks during the day aside from MNTV programming, especially the subchannels.