There's really no reason why you can't use a 1:1 auto polish. Just remember that auto polish is generally abrasive. It's designed to remove surface imperfections, swirl marks, contaminants, old wax buildup, oxidation, etc. And since it's an abrasive (either physically or chemically), it will also remove paint
. Not sure if the clear coat on scale models is thinner than 1:1 car clear coat in any meaningful way. I noticed that Meguiar's Gold Class liquid wax removed some paint from my Mattel Enzo, though.
Most models kept indoors won't experience anywhere near the harshness of real cars, so polishing shouldn't really be necessary. Waxing is a good idea though. Makes dusting much easier, aside from making the models look great.
I use the Zymol Screen kit, which is ostensibly designed for 1:1 polycarbonate headlights and convertible top windows, but is actually nothing more than their mild polish and carnauba paste wax (which has zero polishing/abrasive qualities, so is safe for all finishes, even bare paint). Mequiar's Quick Detail spray and other in-between-waxing sprays also provide a nice shine without potentially harming your paint; seems to be mostly made up of water and not the solvents found in polishes and liquid waxes. None of these come with the cool accessories and packaging of the Meguiar's model-specific kit though.