Easy fix, though it'll take a bit of time and effort on your part... Just watch for when the sparrows go inside the coop and once they're inside, sneak up and close the pophole/door and trap them. Remove from the coop and either relocate or dispose of. In my region, house sparrows and starlings are still classed as invasive exotics, thus don't have the legal protection that most perching bird do...I'm guessing it's the same where you are...
I have this problem with starlings some winters. They go in the chicken house and even try to sleep there at night. I just trap the suckers inside the house and then go inside with a fishing net and catch them one by one. Problem solved.
I'd actually take your house sparrows if I could because they're one of the few 'pests' I'm fond of...I just like their cheerful chatter, tameness, and social behaviour. I USED to have house sparrows, a small colony that would swell to about 60 by the end of each breeding season, dwindle to between 12 to 20 over the winter due to raptor attacks, shrikes, etc. I even put up colourful bird houses for them and fed them and they were happy to use my property as their home base. Alas, a pox virus specific to passerine birds swept through our area some years ago and killed a large percentage of all the resident populations of vulnerable species, including the house sparrows. Only a few survived and their numbers never recovered and they were all gone by the following summer. Still miss them. Oh well...I've got a bunch of mourning doves to support instead now.