If you don't need all of the features of TurboTax Self Employed, you can downgrade from TurboTax Self Employed to Deluxe or another version of TurboTax Online, as long as you haven't paid yet (or registered in a free version) - but please bear in mind that you will need to clear any data which you have entered, and start over in the other TurboTax version. This is the only available method to downgrade versions.
Please see the following TurboTax FAQ, "Can I switch to a lower-priced version of TurboTax Online?":
https://ttlc.intuit.com/replies/4248526
You should be able to import all of your charitable contributions stored in ItsDeductible, without having to re-enter them.
To see some alternate ways you can get to the interview screen in TurboTax Deluxe to import from ItsDeductible, please see epo39b's response to the following question,
"How do i import my charitable contributions from its deductible?":
https://ttlc.intuit.com/replies/5845836