The domain creation script config.sh runs by default in GUI mode, so your X display has to be set appropriately – or there is a console switch to run non-GUI (see Oracle Docs)
oracle@mid1 bin]$ echo $WL_HOME
/u01/app/oracle/product/12.2.1/wlserver
[oracle@mid1 bin]$ cd $WL_HOME/common/bin
[oracle@mid1 bin]$ ls -al
total 76
drwxr-x— 2 oracle oinstall 4096 Jul 2 16:05 .
drwxr-x— 10 oracle oinstall 4096 Jul 2 16:05 ..
-rwxr-x— 1 oracle oinstall 583 Sep 26 2016 config.sh
-rwxr-x— 1 oracle oinstall 578 Sep 26 2016 pack.sh
-rwxr-x— 1 oracle oinstall 582 Sep 26 2016 unpack.sh
-rwxr-x— 1 oracle oinstall 35172 Jun 13 2016 wlscontrol.sh
-rwxr-x— 1 oracle oinstall 16286 Aug 27 2014 wlsifconfig.sh
-rwxr-x— 1 oracle oinstall 807 Sep 26 2016 wlst.sh