The document doesn't mention anything about CSSCAN. Note that both CSSCAN and DMU need to scan the database to analyze the data readiness for the migration but they are implemented very differently.
Thanks for the great post.
This above post is great to see and cleared my all clarification. I have installed PSU patch for my DB 220.127.116.11.0 and applied the opatch 9825461 to use DMU by using the below links.
Have successfully changed the character set to AL32UTF8. Thanks for all your support SRINI, FRAN, WZHANG.