Theoretically... if you have a (trusted) "friend" that has a full unpruned node, one can simply copy the blocks/chainstate and drop them into a new node installation and "voilà", you have your full node without having to download anything, you just have to trust your "friend".
Dont do this.
You can just do a full reindex, right? If your own Bitcoin Core installation verifies all the blocks you copied from your friend, you don't need to trust him anymore.
The issue is not with verifying the blockchain. The issue is you are using hardware that is potentially infected with malware.