Here is the list of all the modded woods which are currently not yet supported by the sawmill.

• Biomes O Plenty
  • fir
  • redwood
  • cherry
  • jacaranda
  • mahogany
  • palm
  • willow
  • dead
  • magic
  • umbran
  • hellbrack
• Quark
  • blossom
  • azalea
  • ancient
• Botania
  • livingwood
  • dreamwood
  • shimerwood
• Ecologics
  • azalea
  • coconut
  • walnut
• Windswept
  • chestnut
  • holly
• Good Ending
  • muddy oak
  • cypress

And here is the list of modded woods which will need to be supported in the future when the mods will update to 1.18.

• Environmental
  • willow
  • cherry
  • wisteria
• Atmospheric
  • rosewood
  • morado
  • yucca
  • kousa
  • aspen
  • grimwood
• Upgrade Aquatic
  • driftwood
  • river
• Autumnity
  • maple
• Endergetic Expansion
  • poise

I will keep updating this issue as mods update.

I updated the list. I added ancient tree from Quark, chestnut and holly from Windswept, and muddy oak and cypress from Good Endings. I also warn that Abnormal mods (Environmental, Atmospheric, Upgrade Aquatic, Autumnity, Endergetic) will soon update.

The Abnormals mods have updated, and I have confirmed that Environmental lacks sawmill support (judging by how there is no data/create/recipes/compat/environmental/sawing folder in the repo), but Atmospheric and Upgrade Aquatic have it. In addition, wood cutting recipes for Quark's ancient and bamboo wood types are still missing.

It also would be nice to see support for Nether's Exoticism's jabuticaba and rambutan wood types.~

Not sure how many of these I have fixed and I'll look through them soon, but keep an eye on #5095
As far as I can tell, I've covered all of the ones on this list that are present in 1.18 if there's any more, please let me know