If you need to uninstall or remove completely OFX plugins please follow these instructions:
On Windows navigate to:
C:\Program Files\Common Files\OFX\Plugins
And remove all plugins you need to un-install from that folder
On Mac navigate to:
/Library/OFX/Plugins
And remove all plugins you need to un-install from that folder
Restart Davinci so the OFX XML list file updates. Open any project save and quit.
Now you can proceed to install new plugins.