Male Skeleton is not included. It will not import into Unreal Engine even when selecting a skeleton. Also, you said in a previous comment it is rigged to the UE skeleton but it isn't.
Viewing post in PSX Rigged Character Bases comments
I just double checked and all the blend files I have include the skeletons. It is using the free rigify add-on, so you might have to enable that.
As for importing to unreal, I use these for my own games pretty frequently and I've never had any issues. When I import I always select the 'thirdPersonMannequin' skeleton that's included in the standard third person template and it works.
If it's still not working let me know and I'll see if I can help
When I import "male_nude_base.fbx" into UE and select the default UE skeleton it doesn't import any skeleton. It does when I import "female_nude_base.fbx" but even then the female skeleton isn't rigged to the UE5 default skeleton and causes the bones to mess up. (I get the "Failed to merge bones" error message and when you regenerate the skeleton it only causes the skeleton to bug out, naturally. EDIT: Just opened the male asset in Blender and there is no skeleton at all. Its a static mesh.
Hmm that's strange. Are you using an older version of Blender? I use 4.1 and 4.2 mainly, but not sure if that matters.
I have to step out but I'll reply when I'm back. In the meantime I added an extra file to the downloads if you want to try importing it directly into unreal engine. I should also mention I don't use unreal 5, I'm still using UE4 (because UE5 is too powerful to make PS1 games imo)
That extra file was rigged with a different system so we will see if that one works. I'm sorry about this! It's the reason I haven't sold more rigged assets, because it's a compatibility nightmare lol