[VXA] Lower Sprite frame/sec (frequency)

I tried to do it with an move event on player but the frequency stays the same, so my question is can i change that on one of the main scripts somehow or do i need a script for that ?

On a player, I don't think this can be done without a script. Just in case that wasn't what you meant,
to do this on an event:

If directly changing the frequency doesn't seem to stick, try this:
On your event that you want to change the frequency of, create a higher page# with the same picture chosen, interaction settings, above/equal/below player, and animation settings, EXCEPT change the frequency to the one you want changed. (Copy any scripting in the event to the new page, if you want them to be able to interacted with the same way.)
On the higher number page, under condition, click next to switch and create a new switch. Now, when you want to change the event's frequency, turn that switch on.

The important thing about using multiple pages on an event is that the game engine will activate the HIGHEST numbered one for which ALL specified conditions are met, and this persists through leaving/entering an area, and saving and loading, as long as those conditions continue to be met; and, if an event can be interacted with, only the scripting on the active page will run.

I try to change the walking frequency from my main actor. I made more mature looking sprites not the chibi style and because the frequency for walking is too high it looks awkward, i try changing that with an event but it didnt affect the actor. Sorry if i wasnt too clear at my 1st post. English isnt my native language

No, it's okay.
I don't expect English speakers on this board, and you did pretty good for not being one
I just wasn't sure if you specifically meant player, or just event.
I'll try to be as clear as possible. You need a scripter to fix this, since you want the "player character" fixed.
If you notice, every event's frequency SAYS that it's based on the player's. (x1/2, x2, etc.)
What you need is to find out if this is explicitly true, or not.
That is:
1) Is base frequency a separate value, accessed by every event? OR
2) Is base frequency linked to the player character, and everything runs off of that?

While I can't script this for you, the result of the above question may give you an idea of what you really need, though you'll need an actual experienced scripter to fix it for you.

If 1 is true, you just need a script that allows you to set PLAYER FREQUENCY via a script call.
If 2 is true, you need a script that redefines all non-player frequencies based on a separately settable value (default, normal player frequency) and THEN the ability to set PLAYER FREQUENCY by script call, UNAFFECTING global frequencies (as, in this script, they are not based on player frequency.)

Again, this is not an admission of anything I can do, but a stepping post to figuring out what must actually be done to reach your goals.

Tnx ☺, so it really is inevitable without a script. Anyway tnx for the info at least i know how to approach this, hopefully i can find someone to make me one