This is the other matcha place I like to visit in Vienna-Matcha Komachi. They are also having a very wide choice of onigiri and matcha. Besides one can eat some hot meals here. My favourites are the soups: from somen to udon. Another big advantage (at least for me) is free wi-fi and afew plugs where I can charge my always dying devices.
Adress and contact: Operngasse 23, Vienna 1040 0676 9111852 FB