Required Vanilla Recipes for Professions

Alchemy Required for leveling:
https://classic.wowhead.com/item=13477
https://classic.wowhead.com/item=6057
https://classic.wowhead.com/item=13480

Blacksmithing Required for leveling:
NONE

Enchanting Required for leveling:
https://classic.wowhead.com/item=11101
https://classic.wowhead.com/item=11039
https://classic.wowhead.com/item=16224

Engineering Required for leveling:
https://www.wowhead.com/classic/item=16042/schematic-thorium-widget
https://classic.wowhead.com/item=16047

Leatherworking Required for leveling:
https://classic.wowhead.com/item=18731
https://classic.wowhead.com/item=5973
https://classic.wowhead.com/item=15725
https://classic.wowhead.com/item=15756

Tailoring Required for leveling:
https://classic.wowhead.com/item=14468
https://classic.wowhead.com/item=14481

Cooking Required for leveling:
https://classic.wowhead.com/item=16072
https://classic.wowhead.com/item=6330
https://classic.wowhead.com/item=16767

First Aid:
https://classic.wowhead.com/item=16084
https://classic.wowhead.com/item=16112
https://classic.wowhead.com/item=16113

Fishing:
https://classic.wowhead.com/item=16083