I needed to run Terminal in x86_64 mode (Rosetta) in parallel with Terminal in arm64 (Apple Silicon native mode), but in the latest versions of macOS, the old way of creating a copy of the Terminal application and selecting Open using Rosetta in Get Info is not available, since Terminal can’t be copied anymore due to security restrictions.
To overcome this, you can use the following command to open any application in Rosetta mode from either Terminal or Automator:
open -a Terminal --new --arch x86_64
This will open a new instance of the Terminal application. To verify Intel emulation mode, running the arch command should output i386 as opposed to arm64 when running natively.