Would diagonally bracing studs on either side of a load bearing stud be safe to remove the load bearing stud?
No. Or yes. It depends on your risk tolerance.
Because the load applies vertically (gravity goes down) there would be both bending and sliding forces at play. Unless you accommodate that with appropriately stiff boards and adequate anchoring it's asking for trouble.
Instead, a conventional header is needed. Trimmer/jack studs along the remaining studs and a properly sized header between is the only good answer. It's also possible that you could use a &quot;flush beam&quot;, which is basically a header integrated with the floor system so that it doesn't interfere with a full-height opening in the wall.
Maybe describe your project as a whole instead of asking such a specific question.