What is the saddest transfer you made?
I know this has been asked and answered many times, but I haven't read any since gen 2. Two weeks ago, I accidentally transferred a "strong" 5000 candy (735ish) eevee that I caught in the wild. I have over 1000 eevee candies, so I effectively transferred a very high and strong umbreon or espeon that I really wanted. I have been hunting high and low to replace it and sadly, I am still dying inside.
Answers
I'm sorry to hear this, it's my greatest nightmare (related to this game of course, I'm fully aware that it doesn't compare to RL tragedies). So far it hasn't happened to me, but I really wish we could put a lock of some kind on a few "most favorite" pokes so they can't be easily unfavorited/transferred.
Hope you find another one, even better. GL!
Two I regret transferring are: my first ever pokemon, 11 cp pikachu, which I transferred while clearing up for mass evolve. And my first wild snorlax which I caught at my birthday; transferred it during last double candy event, even I'm not going to power up any of them now and sitting on about 150 candies, so that two candies are pretty useless.