Legacy Confusion Exeggutor- Solar Beam or Psychic?

Definently, especially for a zam solo.

In short psychic is slightly better than solar beam

In long

Assume 100 ivs at lvl 40
Eggy attack:248
Machamp defence 177

Confusion:
Power:20
Time 1.6
EPS 9.38
Damage per confusion
Floor(0.5*20*248/177*1.2*1.4)+1 = 24
EPM = EPS*T
EPM = 9.38*1.6 = 15
100/15=7

7*24=168
7*1.6=11.2

Psychic:
Power = 100
Time = 2. 8

Damage per psychic:
Floor(0.5*100*248/177*1.2*1.4)+1 = 118

Cdps w/ psychic
(118+168)÷(2.8+11.2) = 20.4

Solar Beam:

Power=180
Time=4.9

Damage per solar beam
Floor (0.5*180*248/177*1.2)+1 = 152

Cdps w/ SoB

(152+168)÷(11.2+4.9) = 19.9

So against Machamp Confusion+psychic has a cycle dps of 20.4 and Confusion+solar beam has a cycle dps of 19.9

Exeggutor with Confusion and Psychic is a slightly worse Alakazam, Espeon or Gardevoir for soloing Machamp. (What is a Mewtwo?)

Exeggutor with Confusion and Solar Beam was a great generalist (notably against Blissey) in the pre-legendary, CP-creep era.

Solar Beam is clearly better, but if you want a defender, you can get one Seed Bomb.

Against Machamp, both are pretty close lol.