The ps3controller and sixaxis are the ones you need to install, but not at the same time. Remove both and try with the sixaxis driver only - both for the PS3 and the clone (for which you might have to enable 3rd party clone support in the driver).
I don't think the dongle will help, the Bluetooth connection should be ok on the 3B+ model.
How did you install your RetroPie system ?
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