I kept losing track of trainers, so I decided to search through the game files and create a list.
I figured I might as well post it here in case anyone else finds it useful.

It only lists each character's starting stats, so the values won't match if they change in later chapters.

This is just for Oaxaca. I might create another list for the DLC later.

Arsenal
Vitality = 40
Willpower = 35
Agility = 30
Strength = 40
Survival = 10
Pistols = 40
Rifles = 40
Hardware = 40

The Bartender
Vitality = 38
Willpower = 30
Strength = 25
Agility = 20
Survival = 10
Charisma = 40
Pistols = 20
Rifles = 20
Software = 25

Uncle Bob
Vitality = 50
Willpower = 50
Agility = 30
Strength = 20
Charisma = 50
Pistols = 20
Rifles = 35
Hardware = 20

Bones
Vitality = 30
Willpower = 15
Strength = 30
Agility = 15
Rifles = 35
Hardware = 20

Boris
Vitality = 25
Willpower = 40
Strength = 5
Agility = 16
Pistols = 5
Rifles = 5
Medicine = 50
Chemistry = 50
Hardware = 50

Carmen
Vitality = 20
Willpower = 20
Agility = 20
Pistols = 8
Rifles = 8
Software = 16

ITIC Cribber
Vitality = 12
Willpower = 22
Agility = 12
Pistols = 5
Hardware = 20
Software = 20

Gaozhong
Vitality = 20
Willpower = 25
Agility = 25
Strength = 10
Stealth = 10
Pistols = 10
Rifles = 10
Hardware = 10

Officer Garcia
Vitality = 32
Willpower = 20
Strength = 15
Agility = 22
Pistols = 30
Rifles = 30
Chemistry = 10
Hardware = 10

Junebug
Vitality = 30
Willpower = 50
Strength = 5
Agility = 20
Pistols = 5
Rifles = 5
Medicine = 35
Chemistry = 50
Software = 40
Hardware = 50

Laughing Coyote
Vitality = 30
Willpower = 25
Strength = 15
Agility = 20
Survival = 10
Pistols = 10
Medicine = 5
Voodoo = 10

Dr. Lee
Vitality = 20
Willpower = 50
Agility = 15
Pistols = 20
Hardware = 50
Software = 50

Leon
Vitality = 32
Willpower = 20
Agility = 20
Stealth = 10
Pistols = 15
Rifles = 15
Chemistry = 20
Hardware = 20

Lilly
Vitality = 15
Willpower = 20
Agility = 30
Stealth = 30
Pistols = 20

Maria
Vitality = 18
Willpower = 50
Strength = 5
Agility = 15
Stealth = 5
Charisma = 50
Medicine = 50
Voodoo = 50

Marvin
Vitality = 45
Willpower = 15
Strength = 5
Agility = 12
Stealth = 12
Pistols = 5
Rifles = 5
Survival = 20
Medicine = 50
Chemistry = 50
Hardware = 50

Mr. Mungo
Vitality = 50
Willpower = 25
Strength = 30
Agility = 20
Charisma = 50
Pistols = 10
Rifles = 50

Ozee
Vitality = 65
Willpower = 35
Strength = 50
Agility = 10
Survival = 30
Charisma = 30
Pistols = 50
Rifles = 10
Chemistry = 15

Rains Through Roof
Vitality = 20
Willpower = 40
Strength = 5
Agility = 20
Stealth = 50
Pistols = 35
Chemistry = 15
Hardware = 30

Ramirez
Vitality = 38
Willpower = 45
Strength = 10
Agility = 22
Survival = 10
Charisma = 50
Pistols = 35
Rifles = 35
Chemistry = 20

Ricardo
Vitality = 40
Willpower = 20
Strength = 15
Agility = 10
Pistols = 5
Rifles = 15
Survival = 50
Medicine = 10

Officer Rolland
Vitality = 36
Willpower = 20
Strength = 10
Agility = 20
Pistols = 30
Rifles = 20
Medicine = 10
Hardware = 10

Slender
Vitality = 32
Willpower = 26
Strength = 10
Agility = 20
Pistols = 20
Charisma = 35

Tio
Vitality = 35
Willpower = 50
Strength = 3
Agility = 35
Stealth = 18
Chemistry = 25
Voodoo = 40

Zac
Vitality = 35
Willpower = 15
Strength = 5
Agility = 15
Stealth = 5
Pistols = 30
Chemistry = 10
Voodoo = 20

Hopefully, I didn't miss anyone or add someone who doesn't actually offer to train you.
I just tried to grab everyone with a "(Train)" dialogue option.

Some of them might need certain requirements fulfilled before they're willing to train you.

There might be a few stats that don't match here... I'm not really sure why.
(ex: Bartender has 30 software in bartenderInit.bsl but in-game he trains to only 25.)

Feel free to let me know if I messed up somewhere.