That's homebrew rules. Homebrew seems to be pretty common with SW and letting people play a faction the way they want. Often the mechanics are tuned poorly and either perform horribly, or are way overpowered as people rarely playtest homebrew rules very thoroughly.

Nothing would prevent you from playing the game any way you want, as long as your group agrees to the homebrew rules. If you wanted an actual marine faction based on the chaos rules, honestly it'd be the exact statline they have as marine scouts except 3+ armor and ATSKNF and no marks.

I would go with the following, using a mix of chaos gear list and some things from the marine scouts. No sniper rifles, keep missle launcher and heavy bolter as heavies, maybe heavy flamer addition. Storm shield/thunder hammer and power weapons available to leader only

Faction Special Rules

And They Shall Know No Fear: Can always test to get up early from pinning, even without nearby friends. Ignore fear and terror.

Counterstrike: in a turn where a space wolf marine is charged, that fighter adds 1 to their combat score in all combats they fight that turn. This bonus to the fighter's combat score is never increased by more than 1 in this way no matter how many enemies charged them. The fighter does not get this bonus from being charged if they were already locked in combat at the time of the declared charges

Leader - Wolf Guard Pack Leader M5 WS4 BS4 S4 T4 I4 A2 LD9 Skill Trees: All except Stealth Gear Lists: Melee, Pistols, Basic, Special Armor: 3+

Trooper - Grey Hunter M5 WS4 BS4 S4 T4 I4 A1 LD8 Skill Trees: Combat, Muscle, Ferocity Gear Lists: Melee, Pistols, Basic Armor: 3+

New Recruit - Blood Claw M5 WS3 BS3 S4 T4 I4 A1 LD8 Gear Lists: Melee, Pistols, Basic Armor: 3+

Specialist - Long Fang M5 WS4 BS4 S4 T4 I4 A1 LD8 Skill Trees: Combat, Muscle, Ferocity, Shooting Gear Lists: Pistols, Basic, Special, Heavy Armor: 3+

Equipment

Hand to hand Weapons

Knife Sword Chainsword Pair of Wolf Claws (leader only) Power Sword/Axe/Fist (Leader only) Thunder Hammer (Leader only) Storm Shield (leader only)

Pistols

Bolt pistol Plasma pistol (Long Fang/Leader only)

Grenades

Frag Krak Melta (Leader only)

Basic Weapon

Boltgun Shotgun

Special Weapons

Plasma Gun Flamer Meltagun

Heavy Weapons

Heavy Bolter Missle Launcher (Frag, super krak, or both)

Ammo

Hellfire Bolts (boltgun/pistol only)

Misc

Clip Harness photo visor Red dot sight Telescopic sight Camo gear