The ESL field in in the private 'christian' based industry is quite small, and christian based schools have completely different requirements for teachers that are not usually based on academic credentials, at least for some subjects.
ESL is (was) a big field around the world. For the most part, high level qualifications, especially a Masters in Applied Language Studies, is required to teach in schools everywhere, likely even in China in the mainstream schools. For example, I taught in the regular high school system, including American International Schools, in Japan, Kuwait, and Ecuador because I had that Masters in Applied Languages. In fact, in Ecuador, I taught computer programming because of that Masters. (I also had some programming experience.) I was able to obtain a regular teacher's licence in North Carolina and taught K12 ESL for the School Board with my Masters as my credentials (Masters in Applied Languages). Keep in mind that I am Canadian.
Because of COVID, there are now very few opportunities for teachers who would be travelling to a non English speaking country to teach ESL.
I taught ESL online for a Chinese company before VIPkid exploded onto the scene. My company required a Masters in Applied Languages, and I earned $25 an hour US. I was involved with students who wanted to succeed on the SAT, IELtS, and other college based exams. VIPkid, for some reason, caught the immagination of the general public in China. VIPkid destroyed the language teaching industry. The 'teachers' in the compnay generally lack credentials. I compare it to a public school system in the US hiring a music teacher to teach math.
So here we are, back to our grass roots in the ESL industry. We have to rebuild our credibility after having it destroyed by the likes of VIPkid. It's going to be a difficult task, as we also face obstacles like COVID.
There is another issue that is not often discussed. Most countries at this time require students to pass a difficult English test before they can be accepted into university. China has decided to back away from this requirement. I expect that countries around he world will also back away from this requirement in the same way that many countries no longer require a certain grade in math before they can apply for some of the programs at university. Most people do not know the reason for this. This has something to do with the discovery/acknowledgement (now generally accepted around the world) that there are certain mutations in the brains of those (math/science) geniuses. I discovered this by accident when I had my DNA test. What does this mean? Basically, some people do have super brains, and no amount of pouring over textbooks will help us become the next Elon Musk. Governments around the world are realizing this and are adjusting their education systems accordingly. FYI, those people with the superbrains belong to a very small mtdna group, and they all know who they are. They are also tracked by scientists (annoyingly so).
To sum up, I don't think that focusing money/time on an ESL career is the best way forward at this time, unless you have a coveted Masters in the field or the praxis credentials.