Hi,
In short: No, HikaShop's Google product plugin works.
In long:
So first, that policy is not yet enforced, so the error is not critical and you should still be able to get your products on Google products even though you have that "warning".
Then, in any case, you can specify flat rates for shipping and taxes or even UPS/USPS/FedEx automatically calculated rates in your Google products account options and you won't have the message either.
Finally, looking here
support.google.com/merchants/bin/answer.py?hl=en&answer=160162
I can see that Google Products introduced recently additional options in their API so that sending complex tax/shippping models like what is possible in HikaShop might be a bit more close to feasible in the future.
We'll have to study that more in depth and already the optinos in your Google Products account should cover a lot of cases.
HIKASHOP ESSENTIAL 60€The basic version. With the main features for a little shop.
HIKAMARKETAdd-on Create a multivendor platform. Enable many vendors on your website.
HIKASERIALAdd-on Sale e-tickets, vouchers, gift certificates, serial numbers and more!
MARKETPLACEPlugins, modules and other kinds of integrations for HikaShop
