I think the answer is basically no. The washout area needs to include the aileron area because if the wing stalls in all of the aileron area, there is no roll control.

Washout is not used on fully aerobatic designs that require as good inverted characteristics as upright. Now to the basically part of the no answer. Simulated washout is possible and quite easy to do on wings with barn door ailerons where there is a servo for each aileron and a spare channel to separate the left aileron to an aux ch. When doing that, the ailerons are given a mix from the throttle so that they start trimming up at perhaps half throttle and become trimmed up perhaps 3/16" at low throttle. This actually makes a nice setup because the model has no washout under power to possibly harm inverted flight, but has some forgiveness when powered down for landing.

There are of course wing tips that can reduce air flow losses on the tip and assist in preventing tip stall by keeping the end of the wing including the aileron area from stalling.