The SD card will make no difference in a factory reset. Its sole purpose is to provide additional storage space for the channel code itself. It allows loading a less used channel more quickly if you have used all of the onboard memory storage space. Beyond that, the SD card provides no advantage to the operating of the Roku. It doesn't make the Roku faster (beyond loading those specific channels faster), and doesn't retain any memory of operating parameters or usage.
When you perform a factory reset (or if you set up a brand new device), as soon as you link the Roku to your user account it will automatically install all channels linked to your account, assuming your device supports the channel. You might need to reenter your user credentials for channels that log in (such as YouTube or HBO Max for example), but the channels themselves will be installed automatically. Note that Roku will also load a few channels you didn't ask for, but you can easily remove them once setup is complete.
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