Considering JDB fixed XFL ( https://xfl.myfootballnow.com/community/1/4406?page=1#27851 ) you now can join without league approval from league admin and good luck .
here are the 16 openings
Buffalo Bills = https://xfl.myfootballnow.com/team/5
Chicago Bears = https://xfl.myfootballnow.com/team/28
Cleveland Browns = https://xfl.myfootballnow.com/team/12
Denver Broncos = https://xfl.myfootballnow.com/team/1
Houston Texans = https://xfl.myfootballnow.com/team/15
Indianapolis Colts = https://xfl.myfootballnow.com/team/16
Jacksonville Jaguars = https://xfl.myfootballnow.com/team/14
Los Angeles (N) Rams = https://xfl.myfootballnow.com/team/22
Miami Dolphins = https://xfl.myfootballnow.com/team/6
New England Patriots = https://xfl.myfootballnow.com/team/7
New York (A) Jets = https://xfl.myfootballnow.com/team/8
New York (N) Giants = https://xfl.myfootballnow.com/team/18
Philadelphia Eagles = https://xfl.myfootballnow.com/team/19
San Francisco 49ers = https://xfl.myfootballnow.com/team/21
Seattle Seahawks = https://xfl.myfootballnow.com/team/24
Tampa Bay Buccaneers = https://xfl.myfootballnow.com/team/31