Sales has two dates: Order Date and Ship Date. Both should be able to use the Date table, which makes Date a role-playing dimension. Power BI allows only one active relationship between two tables, so the second one is inactive: the dotted line in Model view from Sales[ShipDateKey] to Date[DateKey].
An inactive relationship does nothing until a measure switches it on:
Sales by Ship Date = CALCULATE([Total Sales], USERELATIONSHIP(Sales[ShipDateKey], 'Date'[DateKey]))
For that one calculation, the ship-date relationship becomes active and the order-date one steps aside. In a chart by month, Total Sales shows what was ordered and Sales by Ship Date what was shipped.
Edge case: orders that haven't shipped have a blank ship date, so they never land in a month by ship date. Count them separately so they don't disappear from the report.