Hi Rafael,
use getCaption. It takes an enumeration value and returns the caption of this value. The caption is a translatable string
getCaption($NewEntity/TestEnum)
If you indeed want to use the (language specific) value of an enum, you can use getCaption. If you want to use the name, you could use toString. You can use the value in an attribute or the enum itself (eg as a Microflow parameter or variable)