I plan to buy Pixelover but can't find any export example to test with phaser 3. Can I export sprite sheet that are compatible with Phaser 3?

I just purchased PixelOver because the feature list is insane whether it can or cannot integrate easily with Phaser. That said, I am equally interested in the answer.

I've used PixelOver recently to create a spritesheet from a 3D model. When you're exporting, there are tons of options like directions, animations, and a spritesheet option that adds the animation frames into a sprite sheet (either all animations in a sheet, or one sheet per animation and direction), along with options JSON data. I haven't tinkered much with PhaserJS, but it should work if it uses standard spritesheets

Yeah, that is effectively the answer - export a png spritesheet and that's it.