I'm confused at how these specific trades work. Many trainers will have a Pokemon and they will have it up for trading. But they always want something under lvl 10. The Pokemon that they are asking for is always either a legendary or a evolved Pokemon that would be impossible to get under lvl 10. What is the meaning of this?
They are just people who show off their Pokemon. You can't obtain them without hacking, so just ignore them :D
It could just also be a way to show what PKMN they HAVE that they are willing to trade, but aren't asking to trade for anything specific. You're supposed to get in contact with that Trainer and negotiate something with them.
these people are looking for hackers that have those Pokemon. the only way to obtain said low level legendaries and evolutions is to cheat the game. best to just ignore them.