In "C:\Users\yourusername\AppData\Roaming\Opera Software" and "C:\Users\yourusername\AppData\Local\Opera Software", you can:

Delete the "Opera Stable" folder.

Copy the "Opera GX Stable" folder, paste (which will paste it as "Opera GX Stable - Copy") and rename it to "Opera Stable".

Fix the layout of the "Opera Stable" folder to be like this.

Then, when you start Opera One, it'll use everything from the copy of the Opera GX profile that it can.

Something you can play around with.