I got what you said. I'd be careful with this guy and perhaps his reverbs are good, but his videos are deceptive.

At the end of the day those IRs are done using the classic EQ-matching as is done for cabs. A "digital" EQ snapshot if you will. I would instead try some more complete plugins. At least there's BCA ReGuitar and I think another one I don't remember...

This is how this guy make his IRs for transforming-into-another-instrument explained openly by another guy:

 

There's a lot more to what I said before, in case someone is interested I can elaborate more.
Basically you can do EQ and convolution matching of any effect (i.e. EQ unit) using sine sweep/deconvolution. It only captures that linear static EQ-snapshot.
For EQ matching you can also use simply an eq that makes that "average frequency over X seconds". Compare the two and make the EQ-matching. That's what you use for instruments because, well, they're not effects. But who knows what instruments dry sounds he's using...

 

Most of the time I would be using an electric.

 

solid body? or hollow or semi-hollow electric? each will have different characteristics ..
home recording or playing out?
your 1st and best result will always be with the actual instrument.

Its easier to tweak an acoustic guitar and make it sound like a better acoustic guitar,
than to make a solid body single coil guitar sound like an acoustic guitar. it can be done.
but why bother, with guitar prices so low a nice low end yamaha acoustic, can get some nice sounds
with a little tweaking.

if you want the full acoustic sound, get the largest body guitar you can comfortably play. Bass response is reduced in the smaller and travel size guitars.

also by playing an acoustic it will strengthen your fingers and hand and extend your playing time on the electric guitar before you tire out.

The only reason I can really see for trying to get an electric to sound like an acoustic, is if you are gigging on a modest budget and don't have room to carry 2 guitars around.