Yes there are a few XZN [AKA triple square] tools needed. I buy quality tools such as Stahlwille or Hazet
that are quite expensive. I have found that it's not just the size that's important but also the length & the size of drive to get into some places. That is why I only buy the tools when I need them. This can be a problem if you need your van to be going for next day though.
I have noticed that VW are using more torx fasteners on the later cars[post 2003] so that could be another reason not to buy many sets of tools that will never be used.
I haven't bought many, if any VW exclusive tools, in working on my EV or Passat.
I use the craftsman socket for the huge oil filter cap. I have found that i have needed many different sockets: deep, shallow, normal, and different rachets for different spots: hinged, offset, short, long. Same for wrenches, you never know which will work best. I have cheap harbor frienght Stubby wrenches that are awful in hand, but nice to have for the few occassions that i've needed them. I have craftsman racheting wrenches (but will buy gearwrench when i see a deal, with the little flipper selector) as well as combo non-racheting. But I haven't ever done work on either that required VW exclusive tools.
I too bought the cheap auto parts store "triple squares" and insert them into the socket that fits it or wrench.
I just had to buy two sets. First one was a star bit set; sizes t-40 thru t-60. Second was an OEM 12 point Metric set; sizes M6 thru M12. Don't forget to tell them 12 point Metric or they will say they don't have it. You really only need the M12 but I got the 4 pc set for the heck of it. I found both of these at AutoZone at about $26 for both sets. I also had to grab a Hex bit size H17 for the tranny drain plug.