BBQ near Riverwalk in SA?
I haven't found anything in SA that compares to Central TX BBQ but there are a few decent places. Most are far from the Riverwalk - however . .Mr J's on S New Braunfels is just a short, colorful cab ride away.
Mr J's is definitely a dive - and not like a TX BBQ Joint dive . .but a "looks like it's falling down/I can't believe this is a licensed business" type of dive . . so, depending on what you're looking for, it may or may not be for you.
I'm sorry to say there's very little barbecue in San Antonio that compares to the best of Central Texas. There are quite a few other quality options near the riverwalk, but not cue. Two bros. is the best I've found in SA, but that's definitely not a short cab ride. And also just good, not outstanding.