Hello, after a lot of research I've put together this list of what I've heard is essential cosmic marvel reading in chronological order, please let me know if I need to add anything you deem essential

Infinity Gauntlet Omnibus

Infinity Gauntlet Aftermath

Thanos; Infinity Abyss

Marvel Universe - The End

Thanos Redemption

Annihilation Omnibus

Annihilation Conquest Omnibus

Guardians of the Galaxy - Abnett and Lanning ultimate collection 1

war of kings

Guardians of the Galaxy - Abnett and Lanning ultimate collection 2

Realm of Kings

Thanos Imperative

Annihilators

Annihilators EarthFall

Nova - Vol 1 - Origin

Guardians of the Galaxy vol 1 cosmic avengers

Nova - Vol 2 - Rookie

Guardians of the Galaxy vol 2 Angela

Infinity

Thanos - A god up there listening

Revolutionary War

Thanos - infinity revelation

Guardians of the Galaxy - vol 3 - guardians disassembled

Original sin

Legendary Star lord vol 1

Rocket raccoon vol 1

guardians of the galaxy vol 4 original sin