Anytime you are talking about professional sports you have to measure the competitiveness of a team and who they play. The soccer team should join a major organization in order to play the best teams the world has to offer in order to receive the proper respect. Then there should be no argument as to where they stand from a worldwide standpoint.
Are they legit? Are they comparable to any other regional country or even a smaller country? If so, then there is no reason they should not be recognized internationally. Recognizing a soccer team is not a political situation, and people should not make sports a political issue, especially in today's world.
FIFA, the world governing body for drawn into the domestic political turmoil in Spain over Catalonia's effort to become an independent state. Only the citizens of Spain can make that call. Enlisting organizations that exist based on the agreement of recognized nations is equal to a hijacking of those organizations and by definition, violates their organizing principles. Demanding sanction from a group by ignoring it's foundational rules makes no legal sense and is contradictory in it's essence.
The Catalonian soccer team is not worthy of international recognition on the basis that it is not affiliated with either FIFA or UEFA. This team should become a member of one of these organizations to give itself the support and standing it needs to go international. Belonging has worth in soccer associations.
No, the Catalonian soccer team is not worthy of international recognition, because the fact that it is not affiliated with either FIFA or UEFA strikes some doubt into the legitimacy of their club. Because Catalonia isn't a country, this is no different than any other political subgroup demanding to field its own team in international competitions.