You want Key/Mouse Repeater off.
And Keymaps on.
For 95% of your play time.

That way, you can use WASDQE or the Arrow keys to move the main.
Or the mouse, for that matter.
And the slaves will Auto-Follow, as per /Follow

I've gone and made keymaps, for slave movement.
Basically copy the mapped key, "Others Jump".
But instead of Ctrl + Space as the hotkey, and Space (Target: Window All Without Current)... you use Up Arrow, Down Arrow, Left Arrow and Right Arrow as the hotkey and go with targeting the other windows.
If you want, maybe use Insert, Delete, Home, End, Page Up and Page Down.
That gets you Forward, Back, Turn Left, Turn Right, Strafe Left, and Strafe Right.

Anyway, drive with the main.
Slaves follow.

And create mapped keys for anything that you'd want to broadcast to all clients.
Which is the same as Repeater On.
Except you can then also make mapped keys that broadcast to specific clients.
Without needing to mess around with Black Lists.
Plus they can be dynamic and go to the not-current-windows, no matter what window you are in, with default keybinds in the game.