Some notes to know. NHL bylaws state no expansion team granted within 100 miles of existing franchise. So unlike the usual expansion where you'd have to pay the fee, have the owners approve, here you would need unanimous support, plus likely supplement the existing franchise to allow it.
"Section 4.3 Territorial Rights of Members states "No other member of the league shall be permitted to play games...in the home territory of a member without the latter member's consent." i.e., stars could alone veto it.
MLB doesn't define as well, but seen examples from the Expos moving to DC which cost millions over several years and initial broadcast rights of the Nats being owned by the Orioles. And more recently the Giants single handily blocking the A's from moving to San Jose which is 40 miles from San Francisco, even though Oakland is much closer . . .
In 2016 after the opening of Barclays Center which moved the Nets to Brooklyn they revised the territorial rights for NBA teams from 75 miles to 150 miles so long as it doesn't encroach on an existing teams pre-existing 75 mile rights. Again, Mavs could say no
In the NFL there is much less chance, but the rules are . . . "franchise covers 'Home Territory' (the 75 miles surrounding the city limits, or, if the team is within 100 miles of another league city, half the distance between the two cities) and 'Home Marketing Area' (Home Territory plus the rest of the state the club operates in, as well as the area the team operates its training camp in for the duration of the camp" The biggest issue here is Jerry Jones and Legends, they control the marketing rights for several teams, management rights of several others venues, and are building operators for about 1/3. So even in a charger to LA where Kroenke gave the go ahead because he got paid like crazy and gets the charge and annual rent for Sofi . . . Jerry would get a King's Ransom or say no, and most of the league would support him. Just look at the Texan's deal when Houston entered back into the league.
Below I put together a little map showing the boundaries. The Cowboys in Gray with blue border is a tough one to show based on the NFL terming the city limits, and assuming Arlington here, plus the allowance for Frisco with the Star and their training compound. The Rangers in red is based on 41 miles from the current precedent of the Giants v A's. And the final two are straightforward based on Bylaws for the Stars and Mavs.
but the biggest point made above, is at a minimum of 500 million for an expansion fee and 1.5-2 billion for a stadium, who in Fort Worth is putting up that kind of money before compensating the existing rights holder for a new team. I would expect the minimum barrier to entry would be;
NHL - 4 Billion
NBA - 5 Billion
MLB - 7 Billion (cost of stadium much higher, team much closer so buyout will be larger)
NFL - Just for fun lets say 15, since Jerry is going to get paid.
