Export Textures for Unreal Engine

This guide covers the Unreal destination on Export Texture and the matching source on Texture Folder. The files are written with Epic’s recommended T_ texture prefix and one packed ORM file, in the DirectX normal convention Unreal projects normally use.

Setting	Value
Destination	`Unreal`
Filename Template	`T_{name}_{channel}`
Normal Convention	DirectX
Height	Unsigned container

Files written

Shown for a set named oak_bark with all eight roles (how to read these tables). A set with fewer roles writes fewer files.

File	What it holds	Container and depth	Encoding
`T_oak_bark_BC.png`	Base Color in RGB, the set’s cutout in alpha	PNG 8-bit	Color
`T_oak_bark_N.png`	Normal	PNG 16-bit	Packed normal, DirectX
`T_oak_bark_ORM.png`	Packed: R Ambient Occlusion, G Roughness, B Metallic	PNG 8-bit	Linear data
`T_oak_bark_H.png`	Height, remapped into 0 to 1 when it runs outside it	PNG 16-bit	Linear data
`T_oak_bark_E.png`	Emissive	PNG 8-bit	Color

Opacity has no file of its own. The set’s cutout goes into the alpha of T_oak_bark_BC.png. Add Map beside the Not written line writes a separate opacity file when your material wants one.

After export

Import the folder into your project. Select T_oak_bark_N and set Compression Settings to Normalmap.
Select T_oak_bark_ORM and set Compression Settings to Masks (no sRGB). That setting exists for exactly this: it disables sRGB, because a texture used as a mask should not be gamma corrected. On T_oak_bark_H, untick sRGB. Which compression setting suits a height map depends on how your material uses it.
In the material, split T_oak_bark_ORM into its channels and wire R to Ambient Occlusion, G to Roughness, and B to Metallic.
If the normal reads inverted (bumps look like dents under a moving light), tick Flip Green Channel on T_oak_bark_N, or switch Normal Convention on Export Texture to OpenGL and write the folder again.

Reading it back

Point Texture Folder at the folder and set Source to Unreal, or leave it on Auto.

The Normal Convention Auto item reads Auto (DirectX, from the source), so T_oak_bark_N.png comes back the right way up even though nothing in its name records the convention.
ORM unpacks into Ambient Occlusion, Roughness, and Metallic, and so do the longer OcclusionRoughnessMetallic and OccRoughMetal endings some downloads use.
An empty red lane is dropped rather than imported as a fully occluded map, and is listed as Skipped with the reason why.
A cutout in the BC alpha comes back as the set’s Opacity.

Worth checking

Four things here are conventions rather than published rules, and all four are worth a look on your first asset.

Epic documents no filename-driven normal map detection, so do not rely on the _N ending switching the compression setting for you. Set Compression Settings to Normalmap yourself, as step 1 says. The Masks compression setting and Flip Green Channel are both described in Epic’s own documentation.
The DirectX convention is not stated by Epic on any page these settings were checked against. The existence of Flip Green Channel is consistent with it and it is the convention Unreal projects commonly use, so this destination writes DirectX and the row stays editable. Step 4 is how you check.
The ORM lane order is not defined by Epic either. The order used here (R ambient occlusion, G roughness, B metallic) is the glTF and Godot order, and it is yours to wire in the material anyway, which is what step 3 does.
The _BC, _N, _ORM, _H, and _E suffixes are a community convention. Only the T_ prefix is Epic’s: their naming page describes a generic descriptor slot and publishes no texture suffix table. Rename the rows to your project’s convention and save it as a preset.

References

Recommended asset naming conventions (Epic Games): the T_ prefix and the asset naming pattern.
Texture compression settings (Epic Games): Masks (no sRGB).
Texture properties (Epic Games): Flip Green Channel.
Texture import settings (Epic Games).