There exists no OPi PC2 Plus (now -- will come later maybe, will have an H5 SoC and then also eMMC). And the board you were referring to is the worst choice ever since there is not SATA on these boards, it's just a slow and buggy USB-to-SATA bridge.
I know, Xunlong's naming scheme is horrible (but I assume they simply never will change that) since all the meaning depends on the order of 'PC', 'Plus' and numbers.
OPi PC Plus is an extended version of OPi PC
OPi PC2 is an upgraded version of OPi PC (newer SoC and Gbit instead of Fast Ethernet)
OPi PC2 Plus does not (yet) exists
OPi Plus is something you shouldn't buy
OPi Plus 2 is an even worse version of OPi Plus (more RAM and eMMC and also even more expensive)
OPi Plus 2E is a nice board on the other hand
Better rely on linux-sunxi wiki instead (and maybe those articles here written for a reason, eg. https://forum.armbian.com/index.php/topic/1351-h3-board-buyers-guide/ )