Do you pronounce this word with a sounded 't', or no? My dictionaries say 'no'. I think it may be due the strong vowel before the 't'. But, they also don't show a sounded 't' for the variation /ɪnˈkɑ:gnətoʊ/. If the "strong vowel" theory is not correct, how is the word any different from 'ditto', for which the dictionary shows the sounded 't'. Or maybe that's a typo.
Oh, now that I mentioned 'typo', let me ask another question.
One of my dictionaries shows the pronunciation of via.gra ( obviously, with the '.' as an anti-censorship measurement) as /vaɪɚgrə/, that is with an 'r' in the first syllable. I'm pretty sure that this one is a typo, isn't it?
I'm not sure what you mean by a "sounded t." The dictionaries I consulted show the same t sound for both incognito and ditto.
As for /vaɪɚgrə/, I can't speak about the British pronunciation, but that rhotic schwa notation strikes me as a likely typo. It doesn't even make sense in the context.
For American pronunciation, it is /vaɪˈægrə/.
A sounded t , I supposed, would be like t in Spanish or Italian ? Google-Translate can sound out that distinction pretty well, for incognito or any words having t. What does a dictionary do to show a sounded t ?
Perhaps the breathy muted t is one of the distinguishing features of English.
By sounded 't' I meant, 't' pronounced like a quick /d/.
My dictionary shows a sounded 't' with a little line curved upward, under it. (Like a crescent facing up.)
I would call that sound a "flap t." From an articulatory standpoint, it is an alveolar tap. In American English, it is an allophone of the phoneme t.
Speaking fluidly, I would pronounce the t of incognito as a flap t variant as in letter (Am.E.). However, when I use this word, it is often in an emphatic position. In that case, I am likely to pronounce the t as the unvoiced aspirated allophone.
Jim went to the party, but he went incognito. (aspirated)
Cheryl had an incognito rendezvous while on vacation in Greece. (flap)
The more natural reading in American English is with the flap t. Perhaps the use of aspirated t version is a vestige of "schoolboy Latin", and the use of flap t a sign of waning familiarity with elementary Latin.
Similarly, as a beneficiary of schoolboy Latin, I would be likely to aspirate the t in "errata."