We'd built a tool which can traverse data extract the pii data and put back a token into the data. Before one of our allowed systems would read the data we'd swap in the actual data or an anonymized version if we didn't permission to use it anymore. So we sort of get the best of both worlds we can use the actual data of our customers because we require it, but can safely use data for analytics and retain a lot of the statistical variance of our data.
Crazy complex project to work on given our limited resources but very fulfilling in the end.
It should be mentioned that I don't mention the difference between anonymization and pseudo anonymization in the article mostly because I didn't know it was really a thing. I just implemented a solution given or requirements