So some sort of shared storage is needed. This may lead to the need to migrate your software libary.
This is a very simple task once you've seen it. Below I will move the software libary from:
/oracle/software/softlib to a new mountpoint /swlib .
First, go to the Software Libary under Setup > Provisioning and Patching.
Second, observe the software library you have and click Add button to create a new one.
Third, select the old software library and select Migrate and Remove button.
Fourth, in the popup window, select your target software libary from the pulldown.
Observe the confirmation box and click View Job.
The job runs for a few minutes, just wait or get some coffee.
Now the old software library is gone from the Cloud Control:
But it's still on your host:
So you can free up that space by removing the old directory.
Further reading:
https://docs.oracle.com/cd/E24628_01/doc.121/e24473/softwarelib.htm#EMADM11710