Good eye.
Four 2-1/2" pocket screws per leg into the horizontal brace.
Four 2-1/2" HD counter sunk pocket screws (not pocketed) attach the brace to the bench. The screws were driven at a 12.5° angle. Same angl e as the legs 'cuz that's how the drill had to be held. ;-)
I threw some glue at all connection points just for good measure.
Pocket holes are filled here, counter sunk holes were filled later: