I'm sorry, but that's not how shader works in v4.
You need custom renderer for it: https://github.com/pixijs/pixi-plugin-example/blob/master/src/PictureRenderer.js , this repo was created to help with that task.
> because shader have better performance
yes, there's no extra framebuffer for it.
> we use PixiJS
Guys, you really should move to v5 already. Really. Better to place bounty on converting gdevelop than fixing stuff for older versions of pixi. There are only a few people who can help you with v4.