After doing this I got the same result that dumping and restoring with JKSM did, which does import play data correctly (such as total play time for a game, first boot up date & such) but the games and their icons don't get ported over unless I boot them once, which means that games that haven't been boot up display with a grey icon and are labeled as "???" on the activity log, in the titles page they don't show up at all
I know system transfer correclty imports activity log data so I was wondering if there are alternatives to do this, could there be a local titles database that is independent from the activity log, but that gets loaded to get those game icons when using the apps?
Edit: while documenting myself on the 3ds filesystem I came across the F000000B folder which is part of a nand's extdata and should be carrying software library icons, I confirmed this by dumping the source 3ds folder (using JKSM) and restoring it on the target 3ds, what happened is that I lost icons for games that I only played on the target 3ds since the source 3ds wouldn't have those icons, but I kept all the icons for games that were on the source 3ds and that were booted on the target 3ds
Trying this (replacing F000000B folder) with GM9 instead of JKSV results in all icons getting deleted, as if the folder were reset
I think this is what I'm looking for but those files are probably encrypted and I'm not sure what would be the correct way of porting them correctly, or if it's possible at all, but I hope this helps identify the problem ^^
Edit2: I managed to find the issue and solved using GM9, I manually exported the save files for both the activity log and extdata folder (f000000b) from the source 3ds and then imported+CMAC fixed on the target 3ds, every icon and game data has been restored, so the problem with this was JKSM/Checkpoint not importing the save files correctly
If/when you read this I still want to thank you a lot for your time and help, I really appreciate it