To break mental health condition to potential new advisor? I will be meeting with a professor tomorrow who I previously asked to supervise me. I believe he has the right knowledge to assess the standing of my work in the interdisciplinary field I work in and help me moving forward.
He said yes and gave me some suggestions which I partly followed, but the last time we spoke was in May.
I am currently struggling with issues related to mental health (see this question here) and have been in the past months, although it took a while to realize the depth and take action. They are not diagnosed but they probably include a mixture of: low self-esteem, impostor syndrome, anxiety, and acts of self-sabotage. These are linked and the names I feel are not strictly important. I am currently seeing a psychoanalyst (to address the root causes) and the well being/mentoring program of the university (to get practical suggestions and coping strategies). Fighting on.
I seek two things from the professor:

Relevant advice and (within reason) some mentoring whenever my
cross-field preparation is weak.

An external commitment device that provides motivation for work and
help me overcome some of my issues.


I think I have 1. covered, but I am looking for suggestions on how to discuss 2, especially whether I should break the information about my mental health issues with him.
I see two possible ways to go:

I can simply set the pace by saying &quot;I would like to meet every week to discuss my progress&quot; and not mention my (alleged) conditions. This will be enough to set a weekly deadline for myself and would surely be helpful.

I could mention my issues to some extent. One of the reasons I didn't
ask him to meet before is an ongoing self-sabotage/perfectionism
which makes me unwilling to show my work until it has reached a
satisfactory level. I now realize that, essentially, this
satisfactory level is short of publication-grade material and
clearly impossible without expert feedback. I am afraid of course
that this could: sound like an excuse for my absence and lack of
advancement; mark me as a &quot;bad apple&quot;; monopolize the conversation
away from content; be plain awkward; as I write this answer I am also concerned about him having to disclose this information later on.


This is ill-timed, as the meeting is tomorrow (but I wanted to break the cycle of postponing this and I could always go with 1. right above and postpone breaking the mental health &quot;coming out&quot; to a more appropriate time), but any suggestions from you would be a great help.
EDIT
I ended up doing something midway between telling and not. I have hinted at the fact that I was somewhat stressed out and partially disclosed a concrete example (checking a computation for over three days out of a fear it might be wrong). He said he understands this kind of difficulties as well as my need to have someone to talk the fine details over. I believe he caught the implications and was overall very kind and sympathetic. Unfortunately, he will be entering a half-year sabbatical soon and might not guarantee his presence until the start of the next academic years, but said he would like to read what I am working on and pointed me to others who might be of help.
First, congratulations on taking that first step towards recognizing yourself for who you are and seeking assistance to change yourself and get closer to becoming the person you would prefer to be. That is a huge step that many people are not willing to take, and I must applaud you for your courage.

Now, the issue at hand is whether you should reveal your current state of mind to your advisor. That's a delicate and deeply personal issue which can really only be left to your choice. That being said, if I were in your shoes, I would do so. In fact, I did exactly just that, both to my advisor during school and all my supervisors at work, and I benefited greatly from it. (Note that this is personal experience. If your advisor's personality is… less than accommodating, you may have a different experience.)

One of the most important roles of an advisor is to make sure that their students stay on track, both in terms of the scope of their research and their timelines. The last thing a professor wants is to be an inadequate advisor and as a result have a student take longer to graduate or turn out mediocre papers. Of course, this does depend on how busy the professor is, and they may ask other faculty for help or ask you to be mostly responsible for your own work (the last of which is relatively rare but not unheard of).

Psychological issues can cause many problems, including motivation. You can only benefit from having external motivation to keep you from deviating from your intended timeline, especially from someone you respect. At the same time, having that someone understand that you have difficulties will release you from the pressure of wanting to not disappoint that person, which ironically would have possibly caused you to stress out and as a result end up disappointing that person, then get stressed out from that outcome in a vicious cycle. Inform your advisor of your issues, and then together you can work out how to best manage your workflow. Perhaps you might need more frequent reminders, or require a little more detail with advice/instructions. Most advisors that I know love being helpful to their students, and hopefully your advisor will be the same. 

Please note that you wouldn't be using your current state of mind as an excuse. You are already self-aware of your issues, which means that you will recognize when you attempt to avoid doing something and are capable of changing the course of that behavior when it occurs. Having that external motivator could be the extra push you need to help you turn away from avoidance and back to getting things done.

As for the issue of disclosing your psychological condition, it is not required unless it is directly relevant to the matter at hand. In fact, as mentioned in the answer to the question you linked, it can be considered unethical to unnecessarily disclose such information. If your adviser does find it necessary, let them know about your concern and work together to word it so that it minimizes any undue negative connotations.