That's...a whole separate aircraft. That would basically take an equal amount of effort as Kaan to make. It's not even the difference between hornet and super hornet (which basically only shared avionics), the whole design itself would have to change. It's not just "jet but big". This hypothetical Hürjet 2 would not even carry forward the basic shape of the jet.I am still a fan of developing the Hürjet as Hürjet II with 2 GE-404s, with stealth features and internal weapons bay for both land and naval as a multirole fighter for the actual replacement for the F-16. Turkey needs at least 2 different fighters, one a multirole air superiority fighter, and one a multirole workhorse with low maintenance and operating costs.
I doubt that we will produce and use more than 150-200 TAI KAAN for our own needs, the long-term maintenance and operating costs would simply be too high.
The other countries are already moving towards GEN 6 as an air superiority fighter from 2035-2040.
2040:
150 TAI KAAN +50 optional
40 Eurofighter Tranche 4 +20 Tranche 5 optional
300 Hürjet II Stealth +100 optional
150 F-16 Özgür II/F-16 Block 70
100 Anka 3
100 Kizilelma
500+ Akinci, TB2/TB2 AI, TB3, Anka S and Aksungur drones.
That should totally deter any country even Israel from doing something really stupid.
Simply making more Kaans would be cheaper than actually developing what you stated.