How to create a smooth sliding in a multiplayer game or how to replicate a section smooth movement

hi folks,I am creating a FPS game for multiplayer battles,When I was making the slide , I encountered some problems
Question1 :
When I use functions like AddForce() RequestDirectMove(), even if I perform the same task on both the client and server at high network latency, it causes players to constantly be stretched to correct their position.

Question2 :
Let’s abstract this question. In multiplayer mode, if I want a player to smoothly move a certain distance or time in a fixed direction and variable speed, what should I do.

My current solution:
Use Pawn’s AddMovementInput() interface and modify the MaxWalkSpeed of the client and server to the specified value for movement. In fact, this plan performed well in testing. But I hope to use a more elegant solution.

Please forgive my grammar error, I used translation software.