What helped me years ago, was picking two chords, and practice, in slow motion moving back and forth between the two chords. I left the strumming hand completely out of it so I only had to focus on the chord changes. I also wouldn't worry about using a metronome at this point, it may just cause frustration. Don't worry, it will all come together, we all had these challenges in our early stages, just don't give up, and feel like you have to be in a hurry. It's not a race, it's a journey.