Making gravity oscillate like a sine wave

Hey all! i want to find a way to make the Z axis gravity oscillate like a sine wave between 10 and -10. Is this possible? I have a game board and I want gravity to shift toward one player and toward the other who face each other.

I’d also be happy establishing two separate gravity zones in which half of the game board was -10 and the other half was +10

I believe physics’ gravity is just another vector for AddForce.

Nothing stops you from making you own vectors and change them and add them whenever you need.
You can even make a round planet, but in that case you must calculate direction to its center each frame.