If CCS2 uses the same frame as CCX it's going to be "asymmetrical", the right side is about an inch more off center than the left to fit the torque sensor. The rack would have to be bent properly. Actually CCX rack on my bike is a joke it's all skewed to one side because Juiced just took a symmetrical rack and tried to fit that almost as-is. It's an ugly hack.
I have an original Cross Current. They didn’t come with a rack, fenders or lights. I use Blackburn Central 60mm wide fenders on mine with the mudguards removed (they were too noisy). They were kind of a pain to install (required 2-3 trips to the hardware store) but they work well and have withstood a lot abuse. I use an older MTX disc brake specific rack that is no longer in production. I think you want disc-brake compatible rack with adjustable “struts” to fit the CCS2 frame.
The asymmetry of the frame is only noticeable if you stand behind the bike and look at the rack position from that perspective. It doesn’t bother me personally and FWIW my rack fits fine as-is with not hacks/adjustments necessary to make it fit.
The rack just sits about 1/2” to the right of center towards the drive side when viewed from the back. So most disc-brake specific racks should work. Although I do think you want adjustable struts to get it to work on the newer CCS/CCX frames. The mount for the rack struts is placed higher up on the newer bikes.
You want 28/29/700C x 60mm fenders for the CCS2. The bike has 700C wheels (not 26”.) But yeah, Planet Bike Cascadia should work just fine too.
The problem with the rack is attaching the rear fender to it. The rack is skewed. It is off-center in the rear and centered on the frame in the front. When you attach the rear fender to the rack where the rear light is the fender is off-center with the wheel by almost an inch (can even rub on one side of the tire) and the fender is also twisted because the front of the fender is centered. It's very weird, not a good design IMO.