I am an Informatica Data Masking specialist. Informatica delivers an end-to-end best breed solutions for the complete modern data integration. Informatica is the leader in 5 magic quadrants for over 10 years now
I recommend you have a look at Test Data Management…
We are using data discovery for on prem databases (Oracle, Microsoft sql, and DB2) and it is working really fine.
I guess the secret is in tuning and adjusting the data and metadata patterns.