If you've assigned a
localized text table to the Dialogue Manager, it will look for a table entry with the key "Lost 10 gold, gained 50 faction." If it finds one, it'll use the localized version. Otherwise it will show the string directly.
Unlike the Sequence field (which can have localized variants such as "Sequence en" and "Sequence fr"), the Script and Conditions fields don't have localized variants.
If that doesn't meet your needs, you could
register your own C# function with Lua, similar to the ShowAlert("string") Lua function, and use it to localize your text before sending it to DialogueManager.ShowAlert().