Should you add work done for a company from a possibly gray area to your portfolio?

Question

Portfolio

The essence of the question is the following - I made a custom web application for people who sell sports predictions. I ask you not to throw stones, I didn’t see any blatant bullshit there (there are no promises of 100% winnings, surebets, sale of fixed matches or something like that), everything is on a voluntary basis and with risk warnings.
That is, purely legally, in my opinion, perhaps erroneous, at the moment - this site does not violate Russian laws.
But perhaps it's not ethical to be involved in such a thing at all? Plus, my portfolio is available on Upwork (the site is multilingual), it is not known how potential clients from other countries will react to this.
How can recruiters from Russia treat such work in the portfolio? (sometimes I work remotely under a contract)
What would you do?
PS The work itself turned out to be quite interesting and I spent the last month and a half on it, which is why I asked this question.