I transcribed several pieces from a public-domain orchestral score of Swan Lake and uploaded them to Musescore's web site. This would have been ~dozens of hours of work. (For me, starting with almost no relevant training.)

I did this because those particular pieces were significant to me.

But I attracted the attention of another user who wanted to see more public-domain orchestral music on the site, and who contacted me to ask if I was planning to do the entire ballet (no; it's about 600 pages) and if I would take requests.

I responded that I was happy to take requests but wouldn't guarantee that I'd do any work on them. He requested Tchaikovsky's Italian Capriccio, which was a decent guess as to what I might be willing to transcribe (it's the same author)... but I looked into it, listened to the music, and just couldn't muster the enthusiasm to keep working on it.

So yeah, a request might work, but it's only likely to work if you happen to make an excellent guess about what the person would have wanted to do anyway. Think of it like drawing someone's attention to something.