When opening Minecraft on my switch it will be on the screen where it shows the Nintendo switch logo, it will be on this screen for 5-10 minutes. Then it will go to the "Mojang" logo and will be here for another 5-10 minutes. Loading a world does not take this long probably 1 minute at max (depending on the size of the world) When I try to join a second player, after selecting the user it will allow me to play normally, after 30-60 seconds it will start to lag if there is a different player (like someone on mobile) they will be disconnected. After another 2-5 minutes, the second screen will show then I will get an error "a communication error has occurred Please try again later". I have noticed that when I start the game with someone who does not have a Microsoft account signed in it takes the ~30seconds to load, and if they join it takes the normal time. Both of the accounts who are taking a long time to load both have parental controls on their accounts, and they both have 50+ worlds (one with 120+) If more information is needed I can definitely try.