This is a 0$ vortex shaker that you can adapt to any rotary tool (dremel or equivalent)

I have used a broken drill bit that I have inserted "off axis" into a ball bearing extracted from the moving head of an old hard drive.

The 3D printed axis is inserted into the shaft and then the drill bit is hamered in place (no glue required !)

Don't use excessive speed to run the vortex...

It's working impressively well. But bear in mind that you must keep the bottle gently pressed on the top part.

see it into action : https://youtu.be/aqX01hl8PG4