Any pool that value those who mine during low difficulty more? Imagine a pool having 2 people.

A mines for 1 minute when difficulty is 1000. Then B mine for 1 minute when difficulty is 1. Let's for simplicity sake difficulty change from 1 to 1000 to 1 to 1000 to 1 to 1000 every minute. Say they both got the same machine.

Every 1-2 hours the pool solve some blocks.

The way I understand it is that the pool got far more contribution from B than from A. B contribution to solve some blocks is higher because B provides hash when difficulty is lower.

However, A and B will get roughly the exact same payment.

They submit the same number of shares for the same stratum difficulty.

Am I correct here?

This is important for those who are buying nicehash hash to sell to some other pool. Even though you time your buying when difficulty is low you are rewarded as much as anyone with worse timing,

Are there any pool that rewards you more when you mine at lower difficulty?
I would disagree with Murch's answer.

According to https://arxiv.org/pdf/1112.4980.pdf

Only 2 kind of pools do that. PPS pool. And certain variants of PPLNS pool.

I got to ask the guy that author this.