Slow Motion effect - is it possible with fusion?

Yes it is possible.

Design your games frame based and use deltatime to sync all the events correctly.
Doing slowdown is easy that way, just alter your deltaspeed and your game will speed down/up accordingly.

To set up deltatime create two global values and name them to:
deltaspeed
deltatime

Have event:

Always -> Set deltatime to -> ( ( DELTASPEED / 1.0 ) / ( FrameRate / 1.0 ) ) * 60.0
(Multiply with your framerate, if it's 30fps then use *30 instead)

When creating events, for example position of player, pair it to value and when moving the player always multiply with deltatime.
For example sub from value pos_x -> 4*deltatime

This might sound confusing at first, but it's actually simple and super effective and good practice to include deltatime in your projects.

Everthing is possible.
You can use a afterimage effect.
And do delta timer like Please login to see this link. said.

Please make an example ! I tryed it by my self but seems it doesn't work

You can also put your .exe on a Windows 95 machine.
That should produce a hell of a slowdown effect

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Here the mfa boy, idk if it's this what you wanted;

Here's a quick example i did. not the most accurate thing ever but it should give you a basic idea on how it works. shows you how to do it with float movement and direct movement

Delta time is great as well in case your game suffers any unintentional slowdown. It ensures any movements will still move at the correct speeds you intended even if the FPS varies.

thank you guys !

Please, explain more how use deltatime in actions.

For your information, DeltaTime using FrameRate should not be used. Using the timer variable should be used instead. Example (showing accuracy and how to use deltatime) here:
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