Replacing Webcam Footage with Post Production Facecam footage

Can we have an option where, I can record facecam video separately and then replace it with the webcam footage which was also shot through inbuilt camera. now reason behind this.
1. The webcam footage is raw and cannot be visually likeable like youtube final videos.
2. If I shoot separately video. Then I can do color grading and then replace it with the one which was webcam footage.