KineMaster 5 and KineMaster 6 are separate apps so it's not technically possible to transfer the subscription.

If you have an annual subscription purchased in KineMaster 5 and you want to transfer it to our new version KineMaster 6, we will issue an Apple Store Redeem Code that will allow you to use KineMaster Premium in version 6! In order to do so, we need to verify your subscription first, please contact us via Email Support from KineMaster 5 with mentioning "Apple Store Redeem Code" (KineMaster >> FAQ >> Email Support) and we will take it from there! For more details, please check our notice published in KineMaster 5 on how to transfer the subscription from KineMaster 5 to KineMaster 6.

Please note: The Apple Store Redeem Code does not apply to monthly subscriptions, if you have a monthly subscription and you would like to switch to KineMaster 6, please cancel your KineMaster 5 subscription (you can use the subscription until the period you paid for is over), then you can buy a new monthly or annual subscription with KineMaster 6.