what midi foot controller ?????

The Mission Electronics EP-25K works great with the Factor stompboxes and the H9. It comes in the classic crybaby metal housing if you like that style and is available with dual outputs to operate two units at once if desired.

What is the reason for the dedicated switches to every H9? Isn’t it easier to control them with on switch via midi connection? 

I have used the behringer fcb 1010.  It works great.  Takes a few minutes to figure out programming ccs for the fcb 1010.

For the Behringer FCB1010 the expression pedals are assignable too with the H-9?

You can assign each pedal independently for min & max value range and MIDI CC number.  That’s for each of the 100 switch / FCB 1010 preset positions [10 x 10 banks].  The switch can also transmit up to 5 Program Changes, 2 static MIDI CC values (or one alternating set of on/off MIDI CC values), and a MIDI Note value at v=64.  Up to 10 MIDI Channels [one for each message type: PG 1-5, CC 1-2, EXP A-B, and Note] are set globally across the 100 presets.

One undocumented feature is that Program Change #5 is transmitted after the MIDI CC messages.  This doesn’t apply to the H9, but it allows you to change banks of 128 Program Changes on some devices.  There are many more features added if you install the UnO chip.  Mine is a stock setup.  Either way, do yourself a favor & download one of the 3rd-party free editors.