Super Gamer

I tested this in the latest preview (1.18.20.23) and only standard/physical knockback and iron golem knockback have been fixed. Enchantment knockback from punch and knockback is still reduced and treated like regular knockback.

This bug can also be reproduced by some of the other actions that stop sprinting, such as charging a bow or sneaking.

I tried it and it last for the duration of your hitbox. I think this should be works as intended. The animation shows when your riptide hitbox is active and your hitbox is active even if you switch items, so it should still play. Your character still has their hand in front of them, ready to stab/punch anything in front of them with the momentum they have. Switching items also allows you to control damage dealt, allowing fist damage if a good friend gets in your way or sword damage if you just want to do high damage without recharging riptide. My hotbar did not flicker or improperly switch, so this should not be related to MCPE-78355, as this is simply switching items while an animation is playing. I could see this being a bug if the item were to basically leave your hand (this is what happens in Java), but I think this here, the correct animation, should be works as intended.

The player can also sometimes be hit by a mob earlier or from farther away than usual, or the player's hit might not register correctly. This is more noticeable against fast mobs like the phantom, but is hard to test because it doesn't always happen. It can happen with any mob, but you need to be looking out for it since it is subtle. For example, a zombie might hit you from the same distance you can when you run towards it. The most recent case I got of this is I could not hit a sheep right after I had just hit it (it was not red, so was out of its invulnerability time, and I was within 3 blocks of it). I was able to hit it on my second try. I do not know if this is part of this bug or caused by MCPE-97408. It could also be a more subtle and weaker version of MCPE-71243, where the player might see a mob a very small distance from where they are actually at. This could explain why the sheep might not have been hit, as in the world I could have actually been, temporarily, slightly out of range. Desyncing from server could have also caused this though. I have noticed this in 1.16.100, but it probably was in the game earlier than this. It could be part of the cause of MCPE-94726.