You shouldn't lose any data - DateTime is Slightly less accurate (millisecond level) and than DateTime2
I believe there ae other subtle differences with the scope of dates covered as well, and storage differences in SQL as well, but nothing that will affect normal Date functions.
A list of the differences is here https://docs.microsoft.com/en-us/sql...l-server-ver15
After changing them you may need to refresh the links to update the data type mappings in Access in the front end.