You need to amend your 2019 tax return if it does not already reflect the result of the recharacterization of the contribution made for 2019, that result being a traditional IRA contribution for 2019. If the 2019 already shows the recharacterized contribution as being a traditional IRA contribution, either deductible on 2019 Schedule 1 line 19 or nondeductible on 2019 Form 8606, there is no need to amend.
Taxes on earnings are only paid gains attributable a returned contribution, not on gains attributable to a recharacterized contribution.
