Anti-Establishment movements define themselves by two things. The first is that they don't have any strong connections to existing politicians. This allows them to appeal to voters who distrust career politicians in general, but doesn't really say much about their political positions. The second is that they address niche issues and hold viewpoints which do not get much representation from the existing parties.
But which viewpoints these are can be very different from country to country. In Europe, it's often anti-EU, anti-immigration and/or anti-islamism, but there are also anti-establishment movements with other priorities. In the United States there are also multiple movements which label themselves anti-establishment, like the small-state Tea Party movement, the anti-progressive alt-right movement or the anti-capitalist occupyOccupy movement.
If you are looking for a common denominator of all anti-establishment political movements around the globe, then you will usually find that they usually all have some kind of anti-corruption message (presenting themselves as a corruption-free alternative to the "corrupt establishment"), but limiting them to just that would be an oversimplification. You also often hear demands for more direct democracy from anti-establishment candidates. This often fits well into their populist narrative of being "the voice of the silent majority". But most movements and candidates considered anti-establishment have other primary issues. When they have much overlap with anti-establishment candidates in other countries, that's usually more of a coincidence.