The difference between those two types of reports is on how the needed information is shown based on time.
For example:
Legacy reports take the information including the date that is selected to (Ex. 22.2.2023 - 24.02.202) In this dates will be included also the whole date of the 24.02.2023.
Standard report: for the same date format (Ex. 22.2.2023 - 24.02.202) the information shown will be included until the 23.02.2023 at 23:59.