A simple executable that emulates a mouse scroll wheel's up and down movements, via Shift + Up and Down arrow keys. Made in and compiled with AutoHotkey 1.1.
Download and run the EXE from the location of your choice. It's possible you'll have to right click the EXE file and tell it to run as admin.
Once the program is running, while you're holding Shift, use the Up and Down arrow keys on your keyboard. It'll behave as if you're pressing the scroll wheel.
As this was intended as just a third party tool for Bannerlord's menus that lack scrollbars, all my releases will be posted on Nexus mods. https://www.nexusmods.com/mountandblade2bannerlord/mods/4998?tab=files