well, I don't have many options as there are few tutorials for 1.14 atm.
i'd be happy to share my code with you through emails rather than here for my own reasons. PM me your email for the other way around if you're willing to help me.
Define near the player like within x and z distance? Yes I would use the PlayerTickEvent for this. Then check the surrounding chunks in those distances to see if they are loaded then apply the transfer of the values based on a Random number generator.