Here I go. Complicating a simple project. First I removed the side strings and tied the side meshes together using the sheet bend but NO
Next I took away the end loops. Starting at A
(either end) I went across the end row tying into 2 meshes each time.
I tied 20 rows to hake a shoulder strap. To make a simple short handle only tie a couple of rows.
To tie back into the body of the bag I put a loop through the middle of the handle to stretch the netting apart, I first tied into the first 2 loops of the 8 and then back to the handle in the numerical sequence shown.
Clarification of first step in modification