A free mod for Mount & Blade II: Bannerlord, by mylittletantan.

This is a mod that allows you to configure the perk and skill effects. The way it works is by using MCM. This means that the mod can be updated to add/remove perks and skills when the game is updated and correctly update default values after launching/loading a campaign. It is designed to be safe and save-compatible, and will not harm your device. The only thing you need to do is to install the mod, and it is ready to go. It also has a function that allows you to configure the effects of skills, which is not available in most mods. This means that you can configure the effects of skills to any value you want, including a primary bonus and a secondary bonus.