Describe the bug
From issue: #433
1.16.5 still have this issue in nether.

To Reproduce
Steps to reproduce the behavior:
1.Install Biome O Plenty and Antique Atlas.
2.Create new world and go to nether
3.Open the atlas and find some BOP biomes.

Expected behavior
Normal texture like other biomes in nether

Screenshots

Version information (please complete the following information):

• AntiqueAtlas: antiqueatlas-6.2.3-forge-mc1.16.5
• Minecraft: 1.16.5
• Forge: 36.2.34

Fixed in the upcoming version 6.2.4.

Still, were will only be generic textures. For the best experience, you'd need a resource pack supporting BoP.