mysql -h localhost -u $MYSQLLOGIN -p$MYSQLROOTPASS  -t -e '
CREATE USER $USERNAME@'localhost' IDENTIFIED BY $MYSQLPASS;
create database $MYSQLDB;
grant usage on *.* to $USERNAME@localhost identified by $MYSQLPASS;
grant all privileges on $MYSQLDB.* to $USERNAME@localhost';

You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '$MYSQLPASS' at line 1

mysql -h localhost -u $MYSQLLOGIN -p$MYSQLROOTPASS  -t -e "
CREATE USER '$USERNAME'@'localhost' IDENTIFIED BY '$MYSQLPASS';
create database $MYSQLDB;
grant usage on *.* to '$USERNAME'@'localhost' identified by '$MYSQLPASS';
grant all privileges on $MYSQLDB.* to '$USERNAME'@'localhost';"