Hey Plugin developers Im not sure if this would be a easy plugin or not but it is a different one so you make a plugin which all op and if an op gives you it you can have a cape.Im not sure if this is possible or not but it seems quite cool please send me a pm or write something in here if you can make it or want to ask a question I don't mind if you change it a bit or cant make it Thanks Boriscool22
Players can only see capes if they have Spoutcraft. So while the plugin is possible (I think), players would need Spout if they wanted to see their capes.
There is a mod called capeme and players that have this mod will be able to see other peoples capes on servers
The only way for this to be possible is with with either every player having capeme or using spoutcraft as said above.