Asset Downgrader UE5.7
Do you need to migrate assets to a different project that uses an older Unreal Engine version ?
Have you migrated assets to an earlier version of the Unreal Engine and they don't seem to "appear" in the content browser ?
Do you want to make your assets available to people using earlier versions of Unreal Engine ?
Do you want to use Metahumans in versions prior to 5.6 ?
Then what you need is to use the Asset Downgrader to downgrade those assets to the specific version you want.
Asset Downgrader will downgrade assets to 5.7.4, 5.6.1, 5.5.4, 5.4.4, 5.3.2, 5.2.1, 5.1.1, 5.0.3, 4.27, 4.26 . It works by first upgrading the assets to Source Version (5.8), and then applying various patches to the .uasset files in order to make them compatible with the TargetVersion, just without the newer data (i.e. nanite data is removed for a 4.27 downgrade). Do note that features of the newer unreal versions (like nanite on masked materials, new material nodes, new niagara module versions, new blueprint nodes) can't be ported to the old versions.
How it works :
First, backup all your assets as this plugin is highly experimental and in certain situations it may corrupt assets or crash the editor if something goes wrong.
Either have 2 projects, one the SourceVersion and the other with the TargetVersion, or just switch versions for the project you're working with. Integrate the plugin in both projects.
In the SourceVersion project, select the assets you wish to downgrade.
From the Downgrader menu choose DowngradeSelectedAssets.
Migrate the assets by copy pasting the .uassets . Do not use Unreal's Actions->Migrate... because that will resave assets in the SourceVersion format. Alternatively, switch the version of the project to the TargetVersion
If TargetVersion is a 5.0.3 project add
[Core.System]
UsePackageTrailer=True
to Config/DefaultEngine.ini
You will get a crash on opening assets in 5.0.3 if this is not enabled.
On the TargetVersion project add the google drive version of the plugin for that specific target version
Open the TargetVersion project and then the downgraded assets. If there were no errors, the assets should open correctly. Certain assets, in order to be migrated to other TargetVersion projects that don't have the Downgrader plugin, need to be resaved through the plugin ( select all the assets and use the plugin's SaveSelectedAssets option ) inside the TargetVersion editor.
Supported Assets Spreadsheet
In order to downgrade certain assets (or all assets as it's the case for 5.4) you need to use a custom version of unreal engine that has specific engine modifications in order to make downgrading possible. Check the plugin folder ( UE_5.5EnginePluginsMarketplaceAssetDowngraderDownload Custom Engine & Plugin.url) for the link to where you must download both a custom UE5.5 build and a precompiled version of the plugin for this engine version. After downloading the custom engine and integrating the precompiled plugin in the source project's plugins folder you need to switch the source project engine version to this custom engine build. The video tutorial shows this entire process. Also, if you require an older custom engine build like 5.3 do remember that upgrading assets to the latest version is always possible and I always recommend using the latest custom engine build because that's the only one in active development. If that's not feasible for you, please contact me to discuss alternatives.
Asset Downgrader, Unreal Engine, Fab, Asset,
https://www.fab.com/listings/86a0ce48-ff38-493c-906d-8d2297067ee6
