If you mean the ROM then
2008-04-21 Action_Replay_DS_v154_World_NDS-iND
2007-02-11 Pro_Action_Replay_DS_READ_NFO_JPN_NDS-WRG
2006-08-20 Action_Replay_DS_v102_World_NDS-WRG
2006-08-20 Action_Replay_DS_v100_World_NDS-WRG
I am not sure what, if anything, of great interest they will contain. As others speculated the modern ones, if dumped by conventional tools, will contain little more than the protection bypass game (
https://hackmii.com/2010/02/lawsuit-coming-in-3-2-1/ for more on that).
I know some of those working in cheats had various memory dumps they poked around to do things like
http://doc.kodewerx.org/hacking_nds.html#arcodehacks . I don't know how public any of those dumps and anything gained from it ever became.
If were thinking can I run the action replay and use it on my real games then no, you can however do that with nitrohax
https://www.chishm.com/NitroHax/index.html
Some more on that enhacklopedia link above as well.
Personally I would dump saves from my real games and use them to cheat on ROMs/emulators, and maybe then flash the save back, but to each their own.