Can't create new world.

Hello, I have an old server with a lot of plugins and world in 1.14.4 and multiverse core may struggle to create a new world but atleast it does. However I've just made a new 1.15 server with like 5 plugins and every time i try to create a new world it just crashes. Are old server better than the new ones. Atleast after the server is restarted the new world appeares but this is making plugins like skywars reloaded useless because we can't create a map since it creates a new world for it. The cause of this might be that a lot of people are using aternos nowadays and its servers are struggling to keep up with so many people.

Also to make a single map using skywars reloaded i need to restart the server 2 times in the process because aternos crashes