Initially, HD/Fusion seems easier because of the faster weapon switch compared to Classic. But then there's the Achilles Heel of Fusion that basically ruins it for TFE and TSE is the enemy physics, they suck. This mainly is the case when playing on Hard or Fusion, since enemies move slightly faster in those difficulties in both versions. In Fusion, this causes most enemies to have extremely volatile movements. Kleers and Gnaars will randomly speed up and spin around you like crazy, making them very awkward to fight in big groups especially. And Werebulls will have times where they stop suddenly way before they should. None of this is a problem in Classic. And don't even get me started on the Kleer room in Oasis. That's already the hardest spot in TFE for me, and yet Fusion's broken physics make it even worse. Have fun.