Can you explain why?
If you install both as software only, and nothing is running from those homes, sure.
However, the higher version should be installed as upgrade, and perform the upgrade.
Can I ask why you want that ?
When you do the upgrade, you can roll back to the old one.
The cluster is a set of host working as single host, so the Clusterware is on top and control/manage the hosts, if you have 2 cluster on same host the both software cluster will have concurrency disputing who manages the host and this MUST not occur.
2 CRS software are not allowed on the same nodes. There are several init scripts to start / stop CRS. They cannot point to several GRID HOME at the same time. Also, there is a file storing the OCR disk location. It cannot store 2 version CRS information. Hence, 2 version of CRS should not be allowed on same nodes.