Yes. Always the same though (maybe with some variants you write over time). I think the best might be to guide the receiving party so they act exactly like you want.
Example:
"Hello nice to meet you. We are a bunch of junior devs learning to make production code. We'd appreciate if you'd read our PR. However, if at first glance it doesnt look at all like something you'd merge, please simply send us a "nope" and we'll figure out why ourselves with the help of our mentors. Our goal is for you not to spend time on totally off-road PRs.
However if the PR is interesting to you, please proceed like you always do.
You can always reach us via [some form url that's automatically generated for that PR]"
Something like that that someone who can write and think has writen.
Take control at every step to prevent the receiving party to roam freely with the PR so to speak (unless it's decently good), because they might gonna go left and right - and south otherwise. They'll attack you on superficial thing. Make them a smooth funnel so they dont have to talk to nobody to move forward.
That's what came to mind.
P.s. or send them a url they follow entirely.
1. Read the PR in 15 min and come back here
2. How do you like it at first glance? A) very much, it's merged already, B) it's okay but I have feedbacks, C) not at all what we need sorry.
Etc.