I have 3 Golden Comets (same as Red Sex Links) and 4 bantams (Belgian d'Anver cockerel, Gray Japanese bantam pullet, OEGB cockerel, and OEGB pullet). My 3 standard pullets are several weeks older than my bantams. I kept each group in separate brooders but took them out to scratch around together, daily. Next, I constructed two separate coops for each little flock - but allowed them to come out and roam the lawn together each day. Initially, the standard pullets pecked at/chased the bantams incessantly (if they encroached on their space). Given time, they've become quite integrated as one flock. They frequently roam about (standards and bantams, side by side). On the occasion, a standard pullet will still peck at a bantam pullet that is attempting to get food/water (but I usually just place 2 feeders/waterers on the lawn and this helps eliminate the issue). They are all laying eggs now except the OEGB pullet (which I'm expecting any day). -am planning to build one large coop in which to house the entire flock in the spring. (recently acquired 4 more standard chicks - pullets - and am slowly getting them out with all the others...)
Advice: [assuming that you've been housing them separately, and that your standards are all pullets given that they're sex-linked] Let them roam/range together as much as possible. With time, they'll do just fine and establish their own order of things. Scratch is a miraculous thing! Any time scratch grain is thrown out, everyone runs to it!! They usually will mix together without issue in the presence of scratch. Two feeders and waterers make things simple, as they may likely still separate when feeding/drinking. Also, are any of your bantams roos? My li'l bantam roo duo is priceless! They are very protective of the entire flock and do seem to keep order.