How do I import and visualize ply files in Unreal?

there was a plugin but is not no longer usable as is obsolete , how I do in most modern engine?

I would try to import in blender to convert it to FBX and then load it in UE.
I do not know the plugin you are speaking about, if there is source code for it you could try to recompile for your editor version.

I have no option to convert the file, I must use the ply file straight in Unreal , I read it can read now point cloud data , but how ? I can’t find any documentation.

Hello,

It seems ply can store vertices and also triangles not unlike OBJ format.
You can modify the header and only preserve the vertex data, then format it as a XYZ, and finally use the Lidar plugin in UE to read those data LiDAR Point Cloud Plugin Overview in Unreal Engine | Unreal Engine 5.1 Documentation

If your ply has triangle data and you want to preserve that you will have to convert it to OBJ or FBX using script you can find on the internet or free tool such as blender.

Yes that worked. But Can Unreal actually stream the data directly from a website and eventually do that operation text editing ? Or better can unreal receive stream video data from exterior and turn that into a cloud point system?