I can join anarchy servers without logging in and even registration, and I want to create server thad won't require regisration too.
How I must configure my MCGalaxy for it?

i believe true anarchy runs a modified mcgalaxy as well as some special shenanigans from classicube.net that are exclusively made for it. so you can’t recreate the behavior exactly. best you can do is turn verify names off in security tab, then people can direct connect with any name they want.

The anarchy server is given hard-coded special treatment and is the only server that will be the way it is for the foreseeable future. 

Ah well. Ok then.