I wouldn't use an epoxy on trav. Epoxy is more for swimming pools and food prep areas in commercial kitchens where food scrapes and acids will eat normal grout away. You could also look at epoxy as a 2 part as well so esentially the same thing.
You could however use a latex admix for your trav job something like
LATICRETE 1777 Coloured Latex Grout Admix makes a
strong, flexible hard, uniform coloured grout for all types of
ceramic tile, brick, marble, natural stone and agglomerate
stone installations.