Don't try to use Tor. The latency will make you miss shares. A VPN adds minimal latency.

Antminer firmware does not have options for VPN.

Option #1: apply the VPN at the network level. Check if your router has VPN connection capabilities. If not, you can flash OpenWRT router firmware or use a dedicated pfSense router to tunnel traffic through a VPN.

Option #2: use a stratum proxy. Basically, it's a separate PC (or raspberry pi) that pools together the hashrate from multiple ASICs and submits all their shares as a single miner to the pool. It can work with just one ASIC too. Just set your ASICs pool info to the proxy, and configure the proxy to use your pool. Install VPN software on the proxy and tunnel everything thru the VPN.

A good proxy is https://foreman.mn/ wich is forever free for small operations.