Need Guide To Change Aspect Ratio To ALL pictures in Album without changing Other Settings

I loaded a lot of pictures into an LR Album and proceeded to make a lot of edit improvements.

The Crop Aspect Ratio for all pictures was set at "Original".

It should have been set for 3 x 2.

Can I perform a "global / select all" command that will cause all Aspect Ratio of all pictures in the Album to be changed from "Original" or any other setting to a 3 x 2 Aspect Ratio WITHOUT IT CHANGING ANY OTHER SETTING IN EACH PICTURE?

I am using a PC with most recent Windows version.

Thank you for your advice.

Tom