Chronologically it is the following:
The Smoke Room-1915
Route 65-2008
Echo-2015
Arches-2020
However if you are looking for an order to read the story in I recommend starting with Echo and slipping Route 65 in the middle of your echo playthrough. After you are done with Echo you should be good to go with Arches or the Smoke Room as both of these are still in development, while Echo and Route 65 are completed. I highly recommend following the release order, but following Chronology can also be a good way to go if you are alright with The Smoke Room not being finished yet. Read however feels right to you!