Quark contains a feature of vertical slabs: https://quarkmod.net/#features It includes also all wooden slabs.
I cannot find vertical slabs of other wood types when this mod is installed. Maybe this feature was overlooked? :)

Environment:

• Minecraft: 1.19.2
• Forge: 43.1.3
• Every Compat: 1.19.2-2.0.6
• Moonlight: 1.19.2-2.0.24
• Quark: 3.3-371
• AutoRegLib: 1.8-54
• Ecologics: 1.19.2-2.1.9

Expecations:
I expected to see a vertical slab of the coconut wood type of Ecologics.