It doesn't matter if you file joint or separate. You already used your exclusion on your 2020 tax return. Therefore you can't take the exclusion again for 2 years after the closing date of your house.
If your spouse sold their house in 2021, then your spouse can use her exclusion on the sale of their house. But you can't take the exclusion on the sale of their house for two reasons.
1) you took your exclusion on your 2020 tax return.
2) You did not live in the house (I assume) as your primary residence for at least 2 of the last five years you/they owned it, counting back from the 2021 closing date of the sale.
