Hello and welcome!
I had that exact issue when I started -- I even reached out on here several times asking for samples of successful applications and no one replied. If you (or anyone reading this) are a social scientist, I'd be happy to share my application materials with you.
I talked with my advisor about international scholars that he knew and where good work was being done in my field internationally. I also looked through the most recent editions of the international-scope journals in my field, found articles that piqued by interest, and looked at which schools the authors were affiliated with. Then "cold-emailed". After two rejected applications to Australia, I was informed that more STEM-focused fields prefer to work in countries that have English as the primary language and so would have a more competitive field of applicants, so I found researchers in another GROW country and applied there instead.
The entire process is frustrating because NSF doesn't provide feedback on your applications. I had the NSF office at my university read through several drafts of my GROW essay and that seemed to help over time.
Good luck! If you have any further questions, feel free to PM me
I did not know anyone who had applied for GROW when I started the application process, so I can share how I went about it. I first decided which country I wanted to go to and for how long. Then I started looking into researchers at various universities in that country whose work would be complementary to my own line of research. I "cold-emailed" because I did not know anyone in the country I chose to go to, but I was fortunate to get a "yes" from the very first researcher I got in touch with. Just make sure to briefly yet informatively describe to them in your email who you are, what the GROW program is about, and what you would want from them. Then I started brainstorming feasible project ideas and put together an application. I did not have access to any successful applications, so I just carefully thought about the application review criteria, as listed on the GROW site, and made sure to hit all of them. Because I was only going for three months and was also planning on starting my dissertation right after I get back, I decided that my project should be focused on obtaining a training that would be relevant for my dissertation. If I proposed a longer trip, I would likely have come up with a specific research project I could execute abroad, in addition to any important training. But three months just isn't enough time for such project. I also recommend participating in the NSF GROW webinar, which they offer in the Fall. You can PM if me if you have any additional specific questions. It is very true that this forum is pretty much the only place where people share their experiences with the program.
