Odds of the sleeper chairs being added to Beach Club, BoardWalk, Wilderness Lodge and Saratoga Srpings are slim. All 4 resorts have the same layout in the living room and kitchen area. Yet when the BoardWalk was refurbished last year, no sleeper chairs were added. I don't believe there is enough room in the living room for both the sleeper sofa and a sleeper chair.
The one thing they MIGHT have enough space for is a fold-down Murphy bed like the Grand Californian and Aulani, but the fact that these weren't added to BWV doesn't bode well.