Shareplay? Is that video broadcast? If so, you can still probably see the stability of the connection, but broadcasting at the lowest resolution. Which should be 480p, he’ll even lower if the video service allows it. It really depends what the service needs, what the total bandwidth output is getting and so forth. Once you see consistent stable upload for live streaming, then increase the resolution. But 3 mbps... that’s not gonna do 4K uploads, and even it can, you’ll be better off for 1080p, and if anyone complains.. well what mass improvement is 4K gonna do? I’ve yet to see anything worth buying, cause we are still using progressive scan and I discovered it 2006, and progressive scan is older than that. If the 3 mbps is consistent and stable you can make work. I use 2 mbps on my phone and watch videos without issues at any given time or long time. 480p is excellent for a phone except for reading text off of someone else screen, but other than that, 1080p is high enough quality if you can get those upload speeds.
share play? I have no idea what that is, but if I find out it’s less resources needed to make it function, then it may be a wireless stability issue.