Turkish tanks , howitzer and submarine and fighter jet are still not ready to export now so only in drone and helicopters.And ROK already sold thousand k2 tanks, and close to thousand K9.
They also old over hundred FA-50.
After such sales if i were ROK i don't think i would concern myself that much with any competitors.
Not really, if you look carefully, China recently sold hundreds of tanks and hundreds of howitzers to Pakistan.
They also sold 8 submarine for 5 billions.
(Countries don't buy submarine every 5/10 years. They do it once in three decades or so)
Same with BD, CHINA is the largest suppliers of heavy weapons to BD to this day.
There is a strong competition for all kind of systems between Türkiye and PRC, not only drones and helicopters.
In pro-western countries(for example , Poland)there will Turkish -korean competition (these countries will not choose China)in other countries there will Turkish Chinese competition.