I blank 'em off all the time out on the road......useless things
nearly as bad as DPF filters....Grrrrr!"!
the way I do it is undo the bolts between the manifolds, open up the gap and slip in a piece of coke can to block off the hole, do up the bolts and hey presto....no EGR valve.
Doesn't make an iota of difference to the running, but as said, you MAY find a very slight increase in fuel consumption, but I doubt very much you would be able to measure it.
The valve is purely there to attempt to make the engine pump out less CO2, so that the car manufacturers can claim that thier engine is better/greener.