Khai Hirschi

Also, using other tools like shears and pickaxes in your off hand do nothing.

sorry for another comment, but drinking a potion and I assume eating food with a sword in your off hand blocks while you eat/drink.

Also, are you supposed to be able to put potions/food in your off hand? I think so, but it does the weird thing again that I talked about earlier.

apologizes for lack of editing and spamming of comments
Also, with the flint and steel in your off hand and a hoe in your main hand, tapping dirt prepares it for farming, but holding it or tapping again sets it on fire for just a tiny bit before it gets put out. This fire can spread to nearby leaves, etc, though.
Having a bow in your off hand and hoe in your main hand does the same weird thing that the eyes of ender did. Swords in your off hand look fine in this scenario.

Also, a bow in your main hand and flint and steel in your off hand activates both in 3rd person but not in 1st. Replacing the bow with a sword in your main hand looks good though.

Also, throwing eyes of ender with swords in your off hand makes the sword block and bows... they're just weird with eyes of enders. At least 3rd person looks right with a bow in the off hand and eyes of ender in the main hand.

Actually a sword in the main hand does not activate a bow in the off hand.