I posted this in the wrong section and it was closed, so here it goes into this section...

There's this song played on the piano which I've transferred onto Guitar Pro to be played on Guitar and Bass (with both on different clefs)... Now, I'm planning on doing a video with me playing both treble and bass parts but I only have (and can only play) the guitar.

I've (sort of) come up with two solutions(ish)...

If I tune the guitar an octave down, I should be able to play the bass parts, right? But then, it'll sound horrible and I'm not exactly sure how to tune it so low.

Or I can just transpose the bass part on Guitar Pro an octave higher and play it normally on the guitar... But would that be a bit weird?

I don't want to buy any pitch changer or octavers so no suggestions about that please

Any help would be appreciated
There's many free plug-ins with Audacity or any other audio software that can drop something an octave. If not then just EQ the one track with a massive low end.