I dont think there's a way to do it automatically in a sheet worker. You could fake it, very laboriously. Have a sheet worker read the values in the repeating section, copy them all into an array of rows, and sort the rows using javascript. Then with setAttrs, overwrite the existing repeating section row values with the new order. Or delete all the existing rows and add new rows in the proper order. This will mess up any macros people have made linking to items in specific rows though. Since you won't actually be changing the order of the rows, just changing what each row contains.