Maybe something like this .....Yeah, you’ve med me feel ok about removing this. And no, there is nothing transferring the load to the ground.
Now I’m just not sure how to remove the screws from the back side since it’s up against the wall and I only have a few inches to work. Maybe one of those S-shaped screw drivers. Then I guess I’d have to toe-nail (screw) in the new brace.
105 Degree Right Angle Driver Angle Extension Power Screwdriver Drill Attachment with 1/4 Drive 6mm Hex Bit Magnetic Drill Bit Socket Angled Bit Power Drill Tool and Soft Shaft (1 set) - - Amazon.com
Then I would reattach the new brace with a metal bracket hanger.