No HQ-9C is most advanced. 19, 26, 29 are all for high altitude and fast speed targets. Not the same. Like truck and tank are for different purpose. They originally planned for things like SR-71 type super fast and high spy planes or new bombers similar to XB-70 if USAF bought. Satellites for some and nuclear warhead landing phase. Maybe they will modify these old missiles to intercept hypersonic weapons like Americans are developing missiles to intercept our hypersonic weapons. 19, 26, 29 are quite old now. News of testing came out so long ago I cannot even remember. Seems like university days. Quickly those news quiet down and most get deleted.
19 26 and 29 are not suitable for purposes and function of HQ-9C which Chinese military just simply calls HQ-9 still. There is a lot of secrets behind what PLA has when it is about these things. Same with nuclear weapons. No idea exactly how many and what type and modifications.
SM-6 is similar to Hai HQ-9 which is navy HQ-9 and also basically like the best recent type. SM-6 range is said to be below 300km. I think Americans understate this and truly SM-6 is easily 300km+ like our HQ-9C and navy HQ-9.