Well read the post above you and I don't think these work on Ninjhax 1.1.There are two reasons why dynarec isn't available to .3dsx owners.
1) It requires firmware 9.2 or below, and those users can already use .cia.
2) *hax 2.0+ doesn't support it anyway, only older 1.0-1.1 does.
Adding it to .3dsx would only help the small subset of users using 9.2 or below, still using *hax 1.1 and refusing to use .cia for some reason.