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To be honest this seems more like a problem that you solve with infrastructure and not with an art for just one person.
Because the art already requires you to be carrying around some still water, you can't be in combat, need to be looking in sets of three and if contested runs off your stats.
Just buy a xianxia pager for your important people. It'll be about as convenient, could probably be used in combat in extremis, and runs off the stats of someone optimized for the task. Sure, it'll cost money to buy, but that's preferable to using up art slots, build potential and ap for an infrastructure problem.
On a related note, this seems weirdly powerful given how difficult long distance communication is meant to be in this setting. What, were the Weilu the communications backbone before they disappeared? And given that this art is shoved away in a sect's archives it can't possible be that rare.
Just make a scheduled check up time and location/person then you can send messages across the breadth of the Empire, or the world if we assume it has no distance limitations. Combine that with cultivators perfect memories and ability to perceive information and you should have some fairly high bandwidth communication right there.
As in, every ruling clan should have a version of this art and five to ten people just doing this all day or they'll get steam rolled by the strategic and tactical superiority of those that do. It's not an internet or a phone line, but it's not that far off either.