Because I a dumb as hell but I figured it out, eventually.

Synergy in Outpath is when two or more crafting stations love each other very much and make a yellow line in the air connecting them to each other in holy matrimony. <3

This is important as progression is tied to these stations rubbing up on each others as when you complete a synergy it unlocks some locked recipes.

You can be dumb as a stump like me and just put all the stations down near each other to see which have a synergy like a dummy... or...

When you craft a station it literally tells you exactly what other stations it is horny for:

Sure I guess I can type that all out but the thing above probably makes it pretty easy :p This list isn't helpful just saying

• Workbench
  
• Furnace
  
• Anvil
  
• Mill
  
• Cooking Pot
  
• Advanced Workbench
  
• Carpenter Workbench
  
• Imbuing Table
  
• Inscription Table
  
• Amplifier
  
• Cauldron
  
• Summoning Table
  
• Spirit Anvil
  
• Spirit Forge
  
• Other stuff I probably haven't unlocked idk who cares durp

I am proud of all of you and you are great for playing Outpath <3