Frame sizing

So I need some advice. I’m looking at getting a giant roam hybrid to use along side my cove stiffee which is used off-road. Now my cove is a 17.5 frame and I’ve always felt the reach is abit much I am only 5ft 6ish with short arms and a 29 leg. Anyway my lbs has said in the giant roam I need a small frame thats fine but looking at the measurements the small frame is bigger than the cove which is a medium? The reach is more etc I’m confused so will this mean the giant will be more uncomfortable to ride?

Thanks
Tom