The argument that 'X manager hasn't managed in the PL, therefore, it's a risk', is an antiquated one and better suited to the time period in th 80's and 90's where PL football didn't have overwhelming TV coverage outside of the UK, and thus coaches didn't have as easy access to scouting as we do now.
Ten Hag has likely watched more PL footbal than you and I in the last twenty years given both the increased exposure of the PL on European TV, and the very fact that Ten Hag is meticulous when it comes to being a student of the game itself. Do people honestly believe that Ten Hag would come into England and then suffer a culture shock because of some surprise increase in quality or intensity? Do people honestly think that a manager so cerebral and intelligent as him would be caught unaware by the variation in tactical approaches from the Eredivisie to the PL?
If you're smart enough, if you're a student of the game, if you're bright, intelligent and you are tactically minded you've likely already answers to all the questions that the PL can throw at you.