Are these poker chips identical front and back? And is one deluxe set, with the 25’s, enough for 1940 Global?
They are identical front and back, yes.
Most people playing 1940 Global end up getting 2 sets. Your mileage may vary.
One base set = 25 x 1’s, 15 x 5’s and 10 x 10’s
Mini upgrade = 25 x 25’s
When the sets were created it was intended for Anniversary edition and one set has worked quite well for us with that setup, as well as 1942 and 1941.