Yes it can be done in one go, as the documentation states..
For instance for exp/imp method; note 1377213.1 states the following;
"A Database upgrade as part of this migration option *is* supported as the export/import process for higher versions of the Database (for example, 11gR2) supports the import of files exported from lower versions of the database (such as 10gR2). Please review the above documentation for further details.
AS for the RAC related part; (according to our target db releae and EBS release)
you may follow ->
Using Oracle 12c Release 1 Real Application Clusters with Oracle E-Business Suite Release 12 (Doc ID 1490850.1)
Using Oracle Real Application Clusters 11g Release 2 with Oracle E-Business Suite Release 12 (Doc ID 823587.1)
Using Oracle 19c RAC Multitenant (Single PDB) with Oracle E-Business Suite Release 12.2 (Doc ID 2530665.1)
Using Oracle 19c RAC Multitenant (Single PDB) with Oracle E-Business Suite Release 12.1 (Doc ID 2530680.1)
Migrating an Oracle E-Business Suite Database to Oracle Exadata Database Machine (Doc ID 1133355.1)
Migrating Oracle E-Business Suite to Sun Oracle Database Machine Using Oracle Data Pump paper
E-Business Suite on Exadata Oracle Maximum Availability Architecture White Paper October 2012
So, you will combine the related document that I mentioned, and do the migration and RAC configuration accordingly.
I have also EBS RAC migration related blog posts and article in my blog.
(
http://ermanarslan.blogspot.com ). You can read them to get the idea..
For instance;
https://ermanarslan.blogspot.com/2015/03/exadata-ebs-11i-migrating-ebs-11i-to.htmlhttps://ermanarslan.blogspot.com/2015/02/exadata-ebs-11i-exadata-migration-from.htmlhttps://ermanarslan.blogspot.com/2014/02/oracle-ebs-on-exadata-x3-database.htmlhttps://ermanarslan.blogspot.com/2014/02/oracle-e-business-suite-r12-on-exadata.html