I would like to start a PhD now, about ten years after completing my master degree.
I already work in academia, but in a very peculiar situation: I am employed in a teaching-only position in an overseas joint institute (in country B), the links with the university employing me (located in country A) are flimsy, even more so after Covid made travels impossible.
My degree is related but not exactly in the same field that I would like to do the PhD in, like Math to Computer Science. I don't want to do a PhD in the field I did my master in, I actually declined a PhD offer when I was finishing my master because I found that the research in that area was really not a thing for me - I could do it but I found it very dull.
My line manager at the university (country A) - who is not a researcher and is in a completely different field - welcomes the idea and the university would waive any fee of taking the PhD with them, but in practice they would consider reducing my teaching workload only after I have enrolled in a PhD program, which is a problem because due to lack of staff my workload is already very heavy and leaves me very little time for anything else.
Without giving out too much details, I can say that this is UK-style PhD program, so there would be no courses to follow, instead the PhD candidate is supposed to come up with a research question, find a supervisor and then with the supervisor approval they can enroll to the PhD program.
I am having a lot of trouble with this step of coming up with a research question and finding a supervisor. I have tried contacting professors in my department but only one replied; they gave me a talk about their research and basically said "you need to find out what you're interested in", but I feel like I am missing a step before that, like I barely know the options. Everything seems interesting at a first sight, but I would have no idea of what it means to do research in that. Also, my time is so limited that it is hard to dive in into a topic without some mentorship. I have taken online courses in the area that seems most promising to me, because I thought I needed to fill in the gaps before getting to PhD level knowledge, but that gave me nothing about research directions.
From other conversations I feel like in country A there is a natural way for students to get into a PhD, because in their last year they take courses that expose them to the research areas so they can make an informed choice and quite often they pick a topic that is a continuation of their master research. It feels like there is no place for someone coming from a different background, at least not without mentorship, since I have no idea what do I need to learn to get there.
On top of that there is the issue of physical distance from country A and the pandemic making everything more complicated, but doing a PhD in country B where I am located is out of question, not only there are language barriers, but I have serious problems with the academic environment and I have heard too many horror stories to get into that.
I am a bit stuck now, I kind of have the feeling that I would need a mentor before having a supervisor, but so far I had no luck with that. What other options should I consider?
How can one get into PhD level knowledge coming from a different but related field without guidance? Or how else can I get that guidance without a mentor?