Well the whole point of Shadowsocks is that it turns the traffic into HTTPS, so it looks like any other web traffic. This is the main trick here. If any world firewall would block HTTPS traffic, all sites on the internet would break. If you remove the encryption, you are basically just relaying the normal traffic, and it will be detected and blocked.

What you want to do instead is change to a cipher that is extremely fast when software decoded such as “chacha20-poly1305”. It also happens to be the most secure cipher at the moment and only one of 4 used in TLS1.3.

You would start SS with

ss-redir -m chacha20-poly1305