Bedrock Edition:Incompatible Trident Enchantments
Currently, Riptide, Loyalty, Channeling are mutually exclusive enchantments for the trident. However, riptide could be combined with loyalty and channeling in versions 1.2.14.2 and 1.2.14.3. Therefore, many incompatible enchantments were obtainable prior to this change.
Obtaining
While these enchantments were not mutually exclusive, they could be applied to the same trident or enchanted book using an anvil. There are many possible orders and levels of enchantments and the other enchantments: Impaling, Unbreaking, Mending, and Curse of Vanishing can also be applied later.
From beta 1.2.13.8, when Riptide, Impaling, Curse of Binding, Curse of Vanishing, Loyalty, Channeling enchantments were added, to beta 1.2.13.60, riptide, loyalty, and channeling enchantments were not incompatible with each other. They were all made incompatible in beta 1.2.14.3. These compatibilities made it possible to get a trident or enchanted book with Riptide III, Loyalty III, and Channeling I.