If the Italian national enters the UK in 2020, they can register to the EU Pre-settled Scheme, meaning they can live and work in the UK. The Italian national will receive a letter confirming registration that is presented to the UK employer as their right to work check. If the Italian national enters the UK in 2020, they must register to the EU Pre-settled Scheme by June 30, 2021. But we recommend register in 2020 to avoid issues proving right to work issues.
You will need to apply under the Tier 2 visa system in the UK through your employer who will need a sponsorship license.