The pressure at the bottom of the three volumes

First of all, there is a concept that is not clear in the question. Pressure cannot be compared with gravity. Only pressure can be compared with gravity.

Secondly, from the perspective of formula calculation, if the water depth of the three containers is the same, the pressure on the bottom surface will be the same, pressure P = ρgh, bottom surface pressure F = ρghS, where hS is the volume V, But note that this volume is only the corresponding cylindrical volume on the base area. Therefore, in a cylindrical container, the volume is the same as that of water, and the pressure is equal to gravity; in a figure-eight container, the volume is greater than the volume of water, and the pressure is greater than gravity; in an inverted eight-shaped container, the volume is less than the volume of water, and the pressure is less than gravity.