It would help to post the size and load ratings of the tires you consider. If they are a close match to the stock ones, then they fit. These tire sites don't have the complete or always correct info. I am running 265/40/20 symmetric winter tires on my MYP, Michelin Pilot Alpin 5s, and they are not listed as compatible anywhere but they are perfectly fine based on size and load rating, and this is what I research when looking at tires.
That said why put efficiency-designed tires on a PLAID? How are they better than the stock Continentals? I would put an ultra high-performance tire or leave the stock on. I am running Pirelli Weatheractives matching stock 20 inch sizes and they are noisier and less efficient than the stock, but perform pretty well otherwise - I wanted a better snow/ice tire than the Conti's while still driving in mostly snowless conditions 98% of the time.