District Fishwife is a new permanent vendor in Union Market that, like Red Apron is combining retail and prepared foods. I had the chance to attend their opening party, where they served up fish and chips as well as some meaty fried oysters. Last time I was in the market, I didn't see the oysters on the menu, so I don't know if that was a one off.
The fish and chips were fantastic. The fish was excellent...substantial, crispy crust without a greasy feel or taste. No complaints about the fries (er, chips) either. They were served with the standard accoutrements, including a house-made ketchup that didn't really do it for me (needed more vinegar, I think).
There really isn't much to indicate that they are more than a retail fish-monger (like how Red Apron has the bar area), so it'll be interesting to see how they reel people in for the prepared stuff. (Sorry.)