Yes, you can prepare a deceased return in TurboTax Online. It will have to be done under a separate TurboTax account. You can have up to five TurboTax accounts for one email.
If you use TurboTax Online, you can file one federal return with up to five state returns per Intuit Account.
No more than five Intuit accounts and five corresponding federal returns (for example, for a family of five) may be created, purchased, and filed using any one email address.
Per IRS rules, you can only e-file up to five federal returns using the same email address or phone number with personal tax return preparation products.
How do I I add a second personal account?
Logging out if you are in your account.
Choose what TurboTax Online product you want to use for the second return.