Looking for .25 caliber pellet for my airgun

The chart you reference has nothing to do with accuracy, and as far as airguns go, accuracy is everything. There is such limited power, you must put the pellet exactly in the typically small kill zone, even with the .25.

In my AA rifles at approximately the same energy level, the best performers (in order) are the JSB 25.4, the H&N Baracuda Hunter, and the JSB 33.95 King Heavy (original - not MKII).

Every rifle is different. To get the most of it, there is no substitute for trying various pellets, but the JSB domed pellets are usually hard to beat.