This is not an option, if you try to mark one as a duplicate of the other, the system just reports that there are no answers and greys-out the vote button.
Given such a situation then (if you know the answer) you should answer one of the questions (typically the one with the clearest title) then vote to close the other as duplicate of the answered question.
Voting is anonymous, so by definition you should not know who voted or why.
You say you notice that some users have low vote scores, but how do you define low?
Vote count has little relevance to anything, my two highest scoring posts have essentially no technical content, and in fact almost no content at all, whereas some that took some days to answer ...
People vote or don't vote as they see fit, and it's really not for us to be concerned about how much anyone votes. Overall we're a vote-happy bunch, and we also have a tradition of not downvoting excessively.
But whether or not others vote is really not worth worrying about, at least on this site. Both questions and answers generally get enough votes to ...
Apart from the security reason raised by Wang Ki Wun, there are other reasons that Overleaf links should not be accepted as replacements for MWEs. (Some of these you mention in your question, but they bear repeating here.)
First, one of the main goals of the whole network is to be a set of self-contained questions and answers. So in the same way that a link-...
Don't put links to overleaf in public forum, even read-only links will show your email address to everybody
link from this answer https://tex.stackexchange.com/a/506205/195169
click on share and see the mail (I removed name, but you probably recognise that this is your mail)
Since my comment seems to have some votes, I'll add it as an answer:
One thing that is important about duplicates is that it is the question and not the answer that should define a duplicate. Of course at the right level of abstraction, all questions of the form "How do I put language X into a document of language Y" are the same, but I think there is ...
select the answer that benefits the community the most (according to your opinion), hoping that future visitors to your question will find meaning in your choice; or
select the answer that helped you most (based on your situation). Users who visit your post in the future should use their own judgement (and voting) to corroborate choices or find ...
Keep in mind that the processes are set up for the entire network, and in some (many?) cases the nature by one of the largest networks - Stack Overflow - governs the implementation. There you typically deal with a sharks den of coding experts.
Voting still reigns supreme in terms of the Stack Exchange ranking mechanism. We tend to favour the one direction (...