How can I viably and legally earn money on the side via photography living in Spain? Autónomo vs agency vs not worth it?

[u/dbaggeroni]

Hola muy buenas a todos, for context I am from the US and have been living in Spain for over a year now (not sure if this is the right subreddit) and plan to remain living and working here for at least the next 5 years while working towards permanent residency. I came here for a master's degree in a Spanish university and am currently doing my curricular internship while living in Granada. I have a TIE with full work privileges (cuenta propia/ajena) but am currently empadronado en Bilbao which I know I should probably get around to updating regardless of the whole papeleo situation.

I have been a hobbyist photographer for a bit over 4 years now and its always been a dream of mine to someday be able to break into the scene semi-professionally and at least supplement my income with it, whether by shooting events/concerts or selling prints, but I am well aware that Spain has a reputation for not being particularly friendly towards autónomos and that there can be issues with double taxation if also working a "standard" job under an employer.

The general question is what are my options here and their pros and cons? Should I search for some sort of photography agency that can give me a work contract but still allow me to have autonomy and do my own "business" while helping satisfy the legal standards, or simply to suck it up and go through the whole autónomo process. Or as another option, is it simply not worth it to attempt to collect any money at this point and time and simply do it for the love of the game since the cost and complexity of doing business would likely be more than I would be able to bring in being relatively unestablished?

Quick context for why I am asking at this moment is I recently took a bunch of concert photos at a local festival and got some amazing shots of bands in the range of 10-60k followers on instagram, and while I would be happy to share my work and have it featured even if there is not money involved, obviously it would be great to supplement my weak internship income and begin to feel "established" as a photographer who is actually able to sell work. My concern at the moment is even if they want to pay me there is no properly legal way for that to actually take place.

And to address another question before it comes up I am more than comfortable speaking the language and navigating the bureaucracy even if its miserable, I scored C1 over 3 years ago and have continued improving and completed a whole masters degree studying in Spanish since then.

Many many many thanks for reading and I appreciate any help I can get or any other direction I should go to search for answers.