Arsenal officially announce unai emery as new manager

I'm afraid that's not accurate. Unai Emery was actually appointed as the manager of Arsenal in May 2018, not in a hypothetical scenario where Arsenal officially announce him as their new manager.

Emery was appointed as the successor to Arsène Wenger, who had managed the club for 22 years. Emery had previously managed Paris Saint-Germain and Sevilla, and had a successful track record in European competitions.

Emery's tenure at Arsenal lasted for two and a half years, until he was sacked in November 2019. He was replaced by Mikel Arteta, who is currently the manager of the club.