I think I have what you need ...
Depending on whether it is a network what you want to do or a single server. A network is a set of servers connected to each other, forming several modalities and hubs. A server is just a host that focuses on a single modality or topic.
If you need to connect the skyblock server with a network (set of servers), different plugins will be used for this.
Depending on the budget, you can buy premium plugins from skyblock or focused on this.
At a minimum, you will need to make a main map with the skyblock hub and the theme of the server in general.
If we take the Hypixel skyblock as an example, we can do something similar with originality.
Yes or yes a builder is needed (I can do several lobby's and spawns) to make the zones, public plugins configurable to taste, name of the server, its theme, bungeecord (if it is a network) and others.
I have made several minecraft servers of skywars, bedwars, kitpvp and others ...
Maybe I can help out on the job and help the project.
To talk about this more in depth and answer questions, you can talk to me by private message or by my Twitter @Im_koala_ and if you want, I will give you a small demonstration in a few days of a skyblock server configured with what you looking and wanting...
Without more to say, I say goodbye and, have a nice day ;).
L.T.L