Spies

If you're from a different time, then you:

• Possess a bunch of knowledge that most people wouldn't have, some of which may very well be classified in the time you've arrived in.
• Lack a bunch of knowledge about pop culture and current events that most people would have.
• Probably have an accent that sounds slightly off.
• Can't convincingly account for your past, because you literally don't have one in that timeline.
• Have goals which probably look incomprehensible to other people, and therefore are likely to be taken as cover for something more sinister.

How is it possible to travel without being mistaken for a spy?