What they all said is true. But generally speaking too, the rear shock on a stock height Early Bronco will be very close to the correct size in the same position on the rear of a stock height '92 Wrangler.
That's just based, as you already noted, that Rancho does use literally the same part number shock in each of those two applications. So your assumption is correct.
Is it the best for both vehicles? Maybe, maybe not. The valving should be pretty close, both being "utility" vehicles and maybe even near the same weight.
Might not be perfect, but should get you there.
The front shocks are another thing entirely. The Bronco shocks would be way too short for a Wrangler (3" compressed, 7" extended), even though they do have similar mounting strategies.
Not even worth a try unless the Jeep is stock and the Bronco lifted.
BDS does not make their own shocks I don't think (most companies don't) so depending on who they use they may actually be the same shocks, or might be slightly different. If you compare an RS5113's dimensions to your shocks, you should have your answer. They're probably within 1/4" or so, which is acceptable.
Monroe (Rancho) got away from private labeling shocks many years ago, so not likely the same company makes them. But I've been out of touch a long time so don't know if they started doing it again or not.
BDS shared a building with Trailmaster many moons ago so may still be using the same brand shock. Different from Rancho, but most would have similar dimensions by necessity anyway.
Good luck.
Paul