I think the biggest Problem with the Altay Tank regarding the Engine and transmission can be solved, if they go to the Koreans and use the Engine for the K2 Black Panther, afterall there are many similarities with the Altay and the K2, as I have heard the south Korean companies behind the K2, helped in some aspects with the Altay. The First batch of the South Korean K2 Black Panthers used
MTU MT-883 ka501 and used
RENK HSWL 295 TM transmission, this batch(100 tank) was produced between 2014-2015, but then South Korea produced its own engine
Doosan DV27K for the second batch of tanks(106), which they started producing in 2019. They are now in phase three in which they intent to produce them with a fully indigenous powerpack, replacing the RENK transmission with a
S&T Dynamics EST15K, this batch(about 54 tanks so far ordered) they intend to produce from mid 2020 going forward I believe.
This option for Turkey seems to be the best option, and the one with the least restrictions, if turkey orders a huge back of engines, many the south koreans will be willing to allow for a transfer of tech to help develop Turkey's own indigenous engine. Its really the only option outside of getting an engine in the EU, which will come with restrictions. The other option is a Ukrainian engine, which we dont know the quality of as Ukraine has not produced a tank of Altay's caliber and has not developed a new engine for a while, so their capabilities in this area are unknown..
edit: some more specs for the engine and transmission for the K2:
Engine:
Batch 1: MTU MT-883 Ka-501 4-cycle, 12-cylinder water-cooled diesel
Batch 2, 3: Doosan DV27K 4-cycle, 12-cylinder water-cooled diesel
1,500
hp (1,100 kW)
Transmission:
Batch 1, 2: RENK HSWL 295 TM (five forward, three reverse)
Batch 3: S&T Dynamics EST15K (six forward, three reverse, in development(expected mid 2020))