For my BOTW playthrough, I’m attempting to manually take pictures of everything in the game, I even have a checklist made. So far it looks like I have to get these weapons before the game scales the Lynels up:
Lynel Crusher (Regular Lynel)
Lynel Spear (Regular Lynel)
Mighty Lynel Crusher (Blue-Maned Lynel)
Mighty Lynel Spear (Blue-Maned Lynel)
There’s also the Forest Dweller’s Sword (which I can get in one shrine quest in Korok Forest) and the Kite Shield (which is in a treasure chest in an enemy skull base in Hebra). And then there’s a Mighty Lyntel Sword/Shield/Bow set which, thanks to a glitch, I can get in Hyrule Castle.