Probably Codblops, seeing how its graphics aren't even that advanced anymore, apparently. RO2 may strain your system a little more, especially for the higher settings, especially when you consider the quality of animations, effects, the size of maps, minor world and model details, you name it.
If you're doing a PC vs Consoles thing here, RO2 would definitely run better on a PC especially with its mod support and dedicated servers that Codblops doesn't have, if I remember correctly.