If it helps, I'm pretty sure there's a way to go into the settings for a game on playtiles and send the rom file to yourself. I've done that before, since I like the playtiles games but would rather play them on an actual handheld. Let me know if you're able to figure that out
Found it! The Playtiles app isn't easy to understand (even though I work at a helpdesk and I've had my first computer at age 4, 39 years ago) or very responsive, but I finally got it. Here's what I did, on Android :
Log in (duh) > Shop > Playtiles Season 2 > Open in Library > Solastra > Advanced Options > scroll down to Game Files and tap Download ROM (takes about a minute if this is your first time downloading a rom from the app, be patient). The downloaded file will then be in your Download folder (duh again).
I put that downloaded file on my Analogue Pocket and voilà! It works! Thanks for your help and again, for making this game!