Hello! I think what you’re looking for can be done by changing the keyframe interpolation of those keyframes. Right-click on the keyframes, select keyframe interpolation, choose “linear”. Then you can set Easy Ease Out.
My guess it it was set to auto-bezier by default. So in case you want to go back to just the way it was, you can set auto-bezier instead of linear, too.
Hope this helps. 🙂