I have a street-side slide out, but it is almost a foot behind the bulkhead between the cab and the house, so no seat clearance problems on that side. Passenger side, the dinette is built against the bulkhead, but the dinette back can be folded down for clearance to recline that seat.
Issues like these will depend on individual model and model year. Some manufacturers pay more attention to things like this. This slide out/seat clearance issue, and a couple of similar "it just doesn't work for me" things was why friends of ours traded a two slide Sunseeker for an Outlook 29B (equivalent floorplan) after only one season of trying to use it.
If you want a slide out in that position, shop other brands and models and you might find one that works.
Another friend has a fiver with five slides all run by a single hydraulic pump, and to get to her refrigerator she has to run them all out because the one she needs out is the last one to move. Inconvenient for lunch stops. So whether slides can be operated individually is something else to check, for usability.