Will not work
First: Nintendo lifted awhile ago the limit on system transffers you can do.
I and others have tested this:
1. Install all legit cia's to a 9.2 system (A) (hardmodded) (See 1a)
2. Update 9.2 sysnand to 9.8 sysnand (A)
3. System transffered to another 3DS on latest FW (B)
4. Try to redownload all legit cia's again (B)
5. You don't come that far
1a. Works fine,
2a. After updating to 9.8, all games worked fine, checked NNID and says already downloaded, you could wipe them and redownload them (doesn't matter if a NNID was linked before or you linked aftwerwards)
3a. System transffer A to B, smooth without problems, everything transffers, but the legit cia's will not show up, you can't redownload them.
made a backup of the SD before the transffer, using the backup doesn't matter, the legit cia's don't show up.
4a. All legit cia's you installed show can't be redownloaded, you only have the option to buy them.
Conclusion: It doesn't work even if you try 1 game or 2 or all 16 (Europe), something more is missing to be able to system transffer, somehow when transffering it checks and finds you don't legally have the right to system transffer the legit cia installed games, we don't know what and nobody took a look at it again. (took me more then 3 months to try all possible combinations and options cause of the 7 days between transffers)
Note:
If you system transffer from a legit bought pre-installed console to another console with a pre-installed game, it will work, you then can if you bought another 3ds with pre-installed game, system transffer to that and all pre-installed games will transffer and work.
So, It only works when you bought everything legit.
You can have more then 10 pre-installed games on 1 system, that is if you bought those all and system transffered them every time to another console with the 7 days wait each time.
Buy
(All consoles with pre-installed game) A+B+C+E+F+G+H+I+J+K+L+M
System transffer A to B, wait 7 days, System transffer B to C, wait 7 days, system transffer C to D, etc...
M will have all pre-installed games you transffered, playable and redownloadable (You need at least a 32Gb Sd for that)