Current settings:

Phone [A] static IP: 192.168.1.8

Router:Forward (19100-65535) ports to 192.168.1.8

Phone [A] friends can join Phone [A] world.

Phone [B] friends can't join Phone [B] world, because they are connected to the same WiFi and

Router can't forward the same ports to two diff IP at the same time.

NOTE:

Before: I could run up to 4 servers at the same time without problems.

Phone [A] IP 192.168.1.4  Running Server

Phone [B] IP 192.168.1.5 Running Server

Phone [C] IP 192.168.1.6 Running Server

Phone [D] IP 192.168.1.7 Running Server

Router:

ExtPort                IntPort               IP

20001                  19132                192.168.1.4

20002                  19132                192.168.1.5

20003                  19132                192.168.1.6

20004                  19132                192.168.1.7

SHARE_MY_EXTERNAL_IP or HOSTNAME

SkyBlock Server :  MyIp:20001

PvP          Server:   MyIp:20002

Creative  Server:   MyIp:20003

Survival   Server:  MyIp:20004