Now that's a security setup! The question is, how do you manage DEFI (that was the origin of my questioning) if there is no option for signing offline (airgapped pc)?
I don't. The only coins I regularly use and hold long term (or think are worth anything, for that matter) are Bitcoin and Monero, both of which support airgapped wallets, offline signing, and transferring unsigned and signed transactions back and forth. I occasionally buy another altcoin for a specific purpose, but since it is always for a specific purpose I am never holding it long term so I just stick it on one of my hardware wallets for the short time I need it.
I have no interest in DeFi, as I think it will go the same way as the ICO craze, the IEO craze, or all the other crazes we see in crypto - a lot of vaporware, a handful of scams thrown in, the vast majority of coins/tokens/projects dropping to zero, meaning some people who gamble on the right project at the right time will make a lot of money, but most people will lose money, and very little of it will survive long term.