I've been replaying the Ocarina of Time with nephew, and honestly, I do believe that game is hard than either the Wind Waker or Twilight Princess. I actually died once! Pesky newts with swords.
And I personally enjoy the Water Temple. I've never understood the complaint, and have always gotten throughout it without a hitch, even despite not having played the game in like eight years.
Hopefully they make the difficulty somewhere around the Ocarina of Time and Majora's Mask (which was really only difficult because of the time limits, tbh), as opposed to more recent entries in the series.