Highest-lowest stats for Egg Groups

Evolved

Bug:

1. Highest: 600, Mega Pinsir/Heracross/Scizor
2. Lowest: 384, Kricketune

Dragon:

1. Highest: 700, Mega Garchomp/Salamence
2. Lowest: 448, Arbok

Fairy:

1. Highest: 618, Mega Gardevoir/Gallade
2. Lowest: 400, Delcatty(380, Mawile)

Field:

1. Highest: 630, Mega Blaziken
2. Lowest: 330, Delibird

Flying:

1. Highest: 615, Mega Aerodactyl
2. Lowest: 377, Farfetch'd

Grass:

1. Highest: 630, Mega Sceptile
2. Lowest: 405, Parasect/Morelull

Human-Like:

1. Highest: 625, Mega Lucario
2. Lowest: 360, Spinda

Amorphous:

1. Highest: 600, Mega Gengar
2. Lowest: 405, Wobbuffet

Mineral:

1. Highest: 700, Mega Metagross
2. Lowest: 236, Shedinja

Water 1:

1. Highest: 640, Ash-Greninja
2. Lowest: 330, Delibird

Water 2:

1. Highest: 640, Mega Gyarados
2. Lowest: 330, Luvdisc(175, Wishiwashi)

Water 3:

1. Highest: 567, Archeops
2. Lowest: 410, Corsola

Unevolved(second stage):

Bug:

1. Highest: 400, Charjabug
2. Lowest: 205, Cocoons

Dragon:

1. Highest: 452, Sliggoo
2. Lowest: 340, Vibrava

Fairy:

1. Highest: 450, Chansey
2. Lowest: 250, Marill

Field:

1. Highest: 485, Rhydon
2. Lowest: 351, Krokorok

Flying:

1. Highest: 455, Golbat
2. Lowest: 340, Staravia

Grass:

1. Highest: 413, Servine
2. Lowest: 290, Steenee

Human-Like:

1. Highest: 405, Monferno (460, Galarian Mr. Mime)
2. Lowest: 278, Kirlia

Amorphous:

1. Highest: 455, Dusclops
2. Lowest: 278, Kirlia

Mineral:

1. Highest: 465, Magneton
2. Lowest: 390, Boldore, Graveler

Monster:

1. Highest: 430, Lairon
2. Lowest: 360, Loudred

Water 1:

1. Highest: 440, Seadra
2. Lowest: 340, Lombre

Water 2:

1. N/A

Water 3:

1. N/A

Unevolved(first stage):

Bug:

1. Highest: 360, Larvesta (500, Scyther)
2. Lowest: 180, Blipbug

Dragon:

1. Highest: 362, Tyrunt 
2. Lowest: 200, Magikarp/Feebas

Fairy:

1. Highest: 341, Spritzee/Swirlix
2. Lowest: 265, Impidimp/Hatenna

Field:

1. Highest: 410, Ponyta (430, Sneasel)
2. Lowest: 220, Seedot

Flying:

1. Highest: 401, Archen
2. Lowest: 245, Zubat, Noibat, Rookidee

Grass:

1. Highest: 335, Cacnea(435, Tangela)
2. Lowest: 210, Bounsweet

Human-Like:

1. Highest: 350, Mienfoo
2. Lowest: 265, Impidimp

Amorphous:

1. Highest: 340, Koffing
2. Lowest: 198, Ralts

Mineral:

1. Highest: 330, Voltorb (385, Onix/Nosepass)
2. Lowest: 240, Rolycoly

Monster:

1. Highest: 362, Tyrunt/Amaura(385, Lickitung)
2. Lowest: 240, Whismur

Water 1:

1. Highest: 400, Wailmer (410, Galarian Corsola)
2. Lowest: 200, Feebas

Water 2:

1. Highest: 355, Kabuto/Omanyte
2. Lowest: 200, Magikarp

Water 3:

1. Highest: 401, Archen (410, Galarian Corsola)
2. Lowest: 230, Wimpod

Edit (30.12.2019): Sword and Shield changes are added. For lowest stats:
**First stage

*Bug Egg Group is changed from Kricketot (194) to Blipbug(180).

*Fairy Egg Group is changed from Cutiefly (304) to Impidimp/Hatenna (265).
*Human-Like Egg Group is changed from Meditite (280) to Impidimp (265).
*Mineral Egg Group is changed from Roggenrola (280) to Rolycoly (240).
**Second stage
*Dragon Egg Group is changed from Charmeleon and Grovyle (405) to Vibrava (340).
*Human-Like Egg Group is changed from Gothorita (390) to Kirlia (278).