There are are 3 or 4 correct ways.
1. The cheapest, You can offset the girts so the don’t line up.
2. Do book shelf girts.
3 bring one wall’s girts onto the corner post. On top of these girts scab a vertical 2x4 so it it’s inside edge would line up with the original post and provides a face to nail to
4. Use Simpson strong tie angle brackets to attach one girt to the face of the other girt.
With drywall you will have to scab in blocking (I wouldn’t suggest) or use a metal corner backer like straight flex x-crack. You screw the x crack to the girts in the tabs and the drywall get screwed to it and not to the girts any closer than 12” from the corner. It locks the corner together and allows it to float so the corner won’t crack with seasonal and drying movement of the framing.
