Depends how alternate they go. Given the limitated electronics at the time, as Heikki said, a lot of gadgets would not be feasible. Even radio communication had just started around that time and WW1 accelerated development. Vehicles like cars were like the Ford Model T so again how alternate. C4 didn't arrive until the mid 50s and claymores until the 60s (I'm already thinking someone isn't going to have a happy face ).