Hardware version of virtual machine: <virtualMachineName> is not compliant with the highest hardware version on the target.
So what is the message all about, and how can avoid or get rid of it.

Small history - In a customer engagement we were conducting HCX migrations of several different VMs consisting of different OS types and virtual HW (vHW) versions. As the customer had a lot of different VMs with older vHW versions already there we also created VM with vHW version up to the newest available to us v18/v19 (customer did upgrade over the weekend while i was writing the article ;-) ).
When we tried to migrate out TestVM with vHW18 we got the following message from HCX.

This is actually very good that HCX performs the necessary checks before migrating VMs to the destination environment. This basically means we are facing the situation that there are different versions of vSphere in play.
https://kb.vmware.com/s/article/1003746

So check upfront what virtual HW version your VMConAWS SDDC supports.

And compare these findings with your on-premises options you have.

So in the end HCX gives you a warning and that is good, but be aware that you have to wait until your SDDC gets an upgrade before you could migrate VMs with a higher virtual HW version than currently supported.

So the only way to avoid this scenario is to downgrade your virtual HW https://kb.vmware.com/s/article/1028019 or to create VMs that will fit the remote site‘s criteria.

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