Welcome to just Answer!An offset will most likely work.. but you need to know a few tricks to go along with it ---------First you need to find a short offset fitting like this one, not one of the longer ones.Then dismount your box inside the house locate that last..not first.Next fit you outside piece use a threaded conduit coupling, identical to pipe coupling except a little thinner wall and with a smoother finish. and to convert the short offset to a 'box adapter'
remove the thin nut on the left end of it and screw that into the threaded coupling that you attached to the offset piece shown above.Then poke the conduit that runs to the outside of the house into the compression fitting shown on the right side the adapter shown in this pictureThen...rotate the offset so that it lines up with location you want for your box inside...then fit the inside box.I understand that you may have already built the walls and do not have access, so it can be quite difficult. ..sometimes a person has to be a bit resourceful to get all these sorts of things resolved.Look this over, let me know what you think, we can go from there as needed. Phil