You can think of the RES2SV240 as an expander backplane in the form of an adapter card. The RES2SV240 only uses the PCI Express* connector for power (with only power pins connected). You can choose not to plug it in if you supply power from its RA 4-pin power connector.
The RES2SV240 doesn't have any configuration. Either 4 inputs and 20 outputs, or 8 inputs and 16 outputs.
The connected RAID controller configuration utility will be the extent of RAID "system-wide" configuration.
The LSI 9265-8i has been tested with the RES2SV240 so it should work in the 8 inputs and 16 outputs mode, if that's what you're looking for.