Hi,
The user synchronization plugin is an important plugin which should be left enabled. Otherwise, HikaShop won't work properly.
The other plugins are less useful, so you can disable them.
However, these plugins are not your problem.
As long as HikaShop is up to date, these plugins are also up to date and thus they will work fine with Joomla 4, regardless of what the pre check system says. Note also that the pre check system doesn't say that these plugins won't work. It doesn't know. And I can guarantee you these will work on Joomla 4. We have thousands of merchants already using HikaShop on Joomla 4.
Your upgrade problems are from somewhere else. As I said, HikaShop AND its plugins are compatible with Joomla 4.
Of course, even if HikaShop works fine on Joomla 4, if you have other extensions on your website, they also need to be compatible.
Also, if you have customized your HikaShop, then your HikaShop view overrides might not be compatible with Joomla 4.
What you need to do is to setup a copy of the live website, do the update on the copy and check what error messages you have after the update. With the "debug" setting of the Joomla configuration activated, it will tell you where the errors come from. And if you can provide them, we can tell you what to do.