It seems as though nobody is knowledgeable enough to figure out as to why generator points of 2 curves secp and secq256k1 both when divided by 2 generate the same coordinates. Either the so called "experts" and "cryptographers" are clueless as well or they refuse to reveal the secret. Asking questions on other platforms seems to produce the same scripted answers.

Now the only option is to produce very small curves and try all the possible points as G and then try both curves, N, P and then replace P with N to see if the x coordinates of n/2 on both curves can match. There is a relation between G, N and P.

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Secp256k1 :

Secq256k1 :