Is FCPX And Other Software Transferable?

If you bought the application in the App Store it is as simple as downloading it again from your list of purchases.

The application is associated to your Apple id and you can use it on any macs that you own and control.

This is true for Motion as well. For other applications it depends on the terms of their licenses

In your current iMac, go to the App Store application, and click your account at the bottom left.

Do you see FCP among your purchases? If you do, then all is fine.