Emulator

Both the behaviors you described were very much not intended, and caused problems like netplay desync, broken core state (necessitating a restart) and outright crashing.

The architecture of netplay is not and never was designed to gracefully handle players leaving mid-session, and before the changes that you described would often result in a locked up Dolphin instance that would require killing from task manager (though sometimes it would kindly crash instead). I intend to look into enabling leaving and joining mid-session properly at some point, but there are several technical challenges to overcome.

As for changing controller settings mid-session, it is very easy to cause netplay to desync by doing this. Just outright disabling the ability to do this was seen as an acceptable solution, since it's easy enough to just tell people to make sure their controller settings are correct and working before starting the game. If you're in a situation where you need to change between different sets of bindings mid-game, the profile switch hotkeys should work for this.

but yes wile switching from standard to GC wiiu adapter may desync, however this was disabled anyways in Stable 5.0. I think someone made a mistake not understanding that changing your buttons from A to B or B to A was in Dolphin 5.0 and was never a cause of a desync.

and with the force closing the game on netplay
wile YES when someone

started a netplay game
closed game
started again with out all players ending the game and saying yes
would in fact crash the emu but you could of fixed this by making a fail safe code that made the emu check if all players closed the emu before starting the game displaying a error that not all players closed the game yet

all right let me explain why this is a bad thing that it now force closes the EMU on everyone regardless

in games like mario party, someones internet dyed wile the end of a minigame and it was just about to do a in game save on the memory card
Dolphin says GONE with no way to bring it back

Next it crashes WILE its crashes in any game and CORRUPTS The SAVE FILE
and this is Valid for ALL GAMES

on 5.0 stable you were able to

save sate
load it offline
and press A and so on to save it real quick and then save all your progress in the game
it was a very good thing and i wish to see it come back for my games of Mairo Party

oops i ment chashes WIlE its saving in any game

but yeah on 5.0 stable you were able to
save the game even after a netplay crash and thats my problem