I doubt they were using "every feature" that GA had... you should be able to get the equivalent (and more) out of Adobe's interface
This guide should help get you started:
https://experienceleague.adobe.com/docs/analytics-learn/tutorials/intro-to-analytics/transitioning-f...
If you are thinking about trying to backfill data, this might also help https://www.fullstackanalyst.io/blog/adobe-analytics/import-google-analytics-data-into-adobe-analyti...
The first thing you should do is figure out what data they are capturing and what features they are using, then start to build out equivalent reports.
One thing that Adobe's Workspaces can't do is "flat table reports" (https://experienceleaguecommunities.adobe.com/t5/adobe-analytics-ideas/add-quot-flat-table-quot-visu...), but it can do a lot that Google can't do, like create segments that apply to rows or columns and allow you a lot more control over what data you can present.
If you ever used the GA Plugin for Google Sheets, Adobe has a similar plugin for Excel (Report Builder - but it only works on Windows - unless you have "Customer Journey Analytics" which has a newer version which works on both Windows and Mac).
Adobe also has a Date Warehouse export (but you need to be careful with metrics such as "Visits" and "Unique Visitors".. since you can't just add the totals (each row will show the value specific to that combination of data, but the same visit or visitor could have also touched on other rows... the data per row is correct for the context - I hope that made sense).
Good Luck.. and if you have specific questions about replicating an existing report, please let us know.
