Really? I assume you mean that she was laid down earlier than either Mutsu or Colorado, Why the launch delay?
Maryland was laid down in April 1917, more than two years before Colorado and Washington (May and June 1919, respectively) and nearly three before West Virginia (April 1920). I have no idea why they were so far ahead at Newport News, nor why third ship Washington, which was both laid down and launched before fourth ship West Virginia, was the one chosen to be scrapped to comply with the Washington Treaty in 1922, but that is what happened.
As for why it's the Colorado class when Maryland was laid down two years before Colorado, I believe the US Navy numbered its hulls either by when construction was approved by Congress, or as the contracts were awarded, in those days, and Colorado, BB-45, was the first contract on the list. (Also, bear in mind that the Colorado class was basically just an upgunned continuation of the Tennessee class, so they may have been working from an already-established name list.)
What the hold-up was to build her, though, I couldn't tell you. Maybe New York Shipbuilding had another job to finish before they had the dock space to get started. Naval procurement between the World War was sorta the bureaucratic wild west sometimes...