Glacier Express is not included, you have to pay a reservation for this train. But on the same route there are regular regional trains, albeit with changes, but you don't have to pay anything for them, they don't require a reservation. I traveled this way on this route with regional trains.
@Wilkosz Glacier express IS INCLUDED, but you need a reservation. This reservation cost.
This is very important to write it correct, because trains where it is not included, but you get a discount do not need a travel day and have not to be added to the pass.
On the route of the Glacier Express you can avoid the Express and use local trains instead, that do not need a reservation, but you have to change some times the train.
Keep in mind that the SWISS TRAVEL SYSTEM pass included all sorts of public transport in Switzerland like trains, bus, tram and metro. The Eurail One Country Pass Switzerland or Eurail Global Pass include only trains in Switzerland, with a few exceptions.
In your case I would look if a Eurail Global Pass will cost less than two Eurail Passes (one for Switzerland and one the Eurail German Rail Pass Pthis pass includes trains in Germany and to Brussel (Belgium), Salzburg, Innsbruck (Austria), Bolzano, Verona and Venice (Italy)]).