What you are really dealing with is that each client, the client alone, decides to which AP that it joins. There is no central coordination for Wi-Fi, it doesn't exist today. Each client is different. Each OEM has their own algorithm/ special sauce that is used to connect Wi-Fi. The AP has no say. It may make suggestions but the client makes the decision.
What you can do is define what you want the network to do and then pick your most important least capable client and build your AP design around that devices abilities or lack of abilities.
Trust the RRM unless you want to be endless tweaking each and every AP constantly.