A standalone or a plugin, to record in a DAW the output of a midi->midi software?

i am writing a software that transforms midi messages:
midi → midi
On the input it takes midi messages from the controller (e.g. note_on key from a keyboard) and on the output it produces some transformed midi messages (this is to play music with just intonation, e.g. a note_on with a transformed key values and a pitchbend message).

I would like to use a DAW to record the output midi messages.

My question is:

Question: this software should be (1) a midi to midi plugin or (2) a standalone application with an output (virtual) midi port?
The problem with solution (1), is that a DAW will record the input midi messages. To record the output midi messages, the musician has to connect the midi track ouput to the input of another midi track. This seems not so easy.
With solution (2), we just have to select this virtual midi port for the input of a track in the DAW, in order to record it.

Since i am new with audio/midi development, may be i am not aware of other problems or solutions. Is there a preferable solution (1),(2) above or another way?
My first criteria is that it should be easy to used by the musician.