This piece is not about just a single leader who created the crown, but more about the crown itself. The Reichskrone, also known as the Imperial Crown of the Holy Roman Empire, was not commissioned by a single Holy Roman Emperor, but was instead created over a period of several centuries.
The crown's oldest parts date back to the 10th century, but the current form of the crown was mostly completed during the 13th century. It was used by Holy Roman Emperors for coronation ceremonies in Frankfurt from the 14th century until the dissolution of the Holy Roman Empire in 1806.
During this time, many Holy Roman Emperors were crowned with the Reichskrone, including Maximilian I, Charles V, and Ferdinand III. However, none of them commissioned the crown themselves as it was already an established symbol of imperial power by the time of their reigns.
Original 3D Artist: https://www.artstation.com/aj_1
Reichskrone