Sunday will be the first time Emery has faced Arsenal's home fans since leaving the club, with his previous visit in 2021 as Villarreal manager taking place behind closed doors due to the COVID-19 pandemic.
"What they have done since Unai came in, he has made a huge impact at the club in terms of performance... they are still in European competition and played last night. Really impressed by what they have done," Arteta told reporters.
Villa finished seventh last season after Emery joined in October 2022, their first top-10 finish since 2010/11. They are now fifth on 60 points, 11 behind leaders Arsenal.
Emery also completed 1,000 matches as a manager when Villa beat Lille 2-1 in their Europa Conference League quarter-final, first leg on Thursday.
"Unbelievable. And he's done it in so many different countries and contexts," Arteta said.
"He's from very close to my hometown. I have huge admiration and respect for him. Wish him the best after Sunday."
Arsenal lost at Villa in October and, with Liverpool level on points and defending champions Manchester City one behind, Arteta stressed the need to focus on each match without letting the title race be a distraction.
"Every game is going to define what our future looks like," he added.
"It's the only thing possible to look at one game, and one day. Because it's the only thing that maintains your focus and determining the task that you have to do on the day."