Difference in the key schedule of AES for decryption given different orders of operation

Question

As per the Stallings book, the normal decryption of AES has different sequence of transformations [method 1 below], which leads to two separate software or firmware modules and that is undesirable.

However, with the interchange of the ISR and IBS operations during decryption (as they are equivalent), the encryption and the decryption can be given the same form. However, this second method needs a change in the key schedule. I can't find what this new key schedule is.

Encryption (method 1) : ARK BS, SR, MC, ARK, ….. BS, SR, MC, ARK, BS, SR, ARK
Decryption (method 1): ARK, ISR, IBS ARK, IMC, ISR, IBS ….. ARK, IMC, ISR, IBS ARK

Encryption (method 2): ARK BS, SR, MC, ARK, ….. BS, SR, MC, ARK, BS, SR, ARK
Decryption (method 2): ARK, IBS, ISR, ARK, IMC ….. IBS, ISR, ARK, IMC IBS, ISR, ARK

Do the answers of this What are the practical differences between 256-bit, 192-bit, and 128-bit AES encryption? question satisfy you? — kelalaka, Feb 23 '19 at 20:05
As an alternative, you could consider using a mode of operation that uses AES in the encrypt direction for both encryption and decryption; examples of such a mode would be CFB, CTR, GCM... — poncho, Feb 23 '19 at 21:42
@kelalaka my question is not about the key sizes. I wanted to know what kind of change in the key schedule is needed when we want the AES encryption and decryption to have the same structure. I found two related links, but still can't figure out the reference. https://crypto.stackexchange.com/questions/2712/in-which-order-are-the-round-keys-used-during-aes-decryption/2732#2732 — user3656142, Feb 24 '19 at 03:16
https://crypto.stackexchange.com/questions/20519/is-there-an-alternative-aes-schedule?rq=1 I think the answer is explained here — user3656142, Feb 24 '19 at 03:27
I assume ARK is AddRoundKey, BS is ByteSub (nowadays usually called SubBytes), etc? — forest, Feb 24 '19 at 10:13
@forest yes. it seems the change is schedule means the change in the keys due to the InvMixColumn applied before the ARK operation. — user3656142, Feb 24 '19 at 17:57

Difference in the key schedule of AES for decryption given different orders of operation

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