Is this for paid assets?
The general problem we have is that we currently don’t support any import of assets with metadata. ie we support upload of scripts and FBX models but the metadata such as preloading, texture filtering etc is not supported at all for any asset.
So unfortunately, this is not a small job to do and also why we added the copy and paste of assets between projects.
That allowed users to copy an asset (and related assets) from any project they can access (eg public projects) into their own with all the meta data intact.
I do agree that importing and exporting assets would be great and chances are that it would need to be in zip archives. eg templates with the JSON hierarchy and related assets such as textures, models, etc. When the zip is uploaded, it will handle the remapping of ids as it does now with copy and paste.
In your situation, if I wanted to build a website now of assets:
If they are free:
Have public projects of the assets that people can copy between projects that are linked from the site. I’ve done this here with the touch joypad for example: Touchscreen Joypad Controls | Learn PlayCanvas
Users can copy a single folder to their project and import the template into the scene in a few clicks.
If they are paid assets:
This is not ideal and a complete workaround. I would export the project as an archive and have the zip downloadable. Users will download this, import the project privately and then copy and paste.
There’s also questions and issues around updating existing assets as we don’t currently support overwriting existing assets on copy and paste.