They should be fairly close at full power. Reported specs put the Alien Bees B800 around 5600K, and the Elinchrom RX 600 around 5600–5650K, with normal variation in that range. In practice, that means they’re usually close enough that any difference is within a typical tolerance.

The bigger issue is power setting: many strobes shift color somewhat as you reduce power, and Alien Bees are often noted as shifting more than some other systems. So if color consistency matters, don’t rely only on nominal specs.

Best approach: test the actual setup. Shoot a gray card under each light and check white balance/color in post or with a meter if available. If you see the B800s shifting when turned down, one workaround is to keep them closer to full power and reduce output with neutral-density material or by changing distance/modifiers.