Saudi club Al-Hilal have made an approach for the England striker, and Emery confirmed that formal offers had already been submitted, with six of the starting XI that won the Europa League for Villa two months ago now having left, or being close to leaving, the club this summer.
"We have an issue with him, it's clear. He is our player. We have had offers for him," Emery said. "I don't want to sell him but it can change because if it's a good option for him and the club and I can replace him in the squad, this is the routine we have and we did before with the players who are leaving.
"With Ollie, he is here, for me he is a fantastic striker, we have always believed in him.
"Now he is our player, there are 10 days more or less to finish the transfer window, we will see what happens, I'm happy with him, if he is staying with us he will continue playing his level.
"If he leaving it's because it is good for three ways, one is him, another is the club and another is the team."
The 30-year-old has scored 108 goals for Villa since arriving from Brentford for £28m in 2020 and remains the club's record Premier League scorer, but he would become the latest high-profile departure in a summer that has already seen Ezri Konsa join Arsenal for £51m and Morgan Rogers move to Chelsea in a British-record £117m deal, with Youri Tielemans and Lucas Digne also exiting Villa Park.
Goalkeeper Emiliano Martínez could also depart, though his proposed move to Juventus collapsed after the two clubs failed to agree a fee. Villa have already brought in Japan international Zion Suzuki from Parma for £30m as their new first-choice goalkeeper, and Martínez will be absent from Sunday's Premier League opener at Brighton having had just one training session since returning from his post-World Cup break.
"Martinez transmitted to us the possibility to have another challenge in his career," Emery said. "Even last year, he was thinking in case he can have one possibility to change for his challenges.
"He didn't do it last year and he performed fantastic with us. This year, again, he transmitted us the possibility to have another challenge and we decided to sign Suzuki because I think he's a fantastic goalkeeper."
Villa's rebuild is not confined to the first team. Rochdale have signed midfielder Kane Taylor on a loan deal until January, with the 21-year-old yet to make his senior debut for Aston Villa despite scoring for the club's under-21 side in a EFL Trophy defeat by Wigan on Tuesday. He scored twice in 16 League Two appearances on loan at Oldham last season.
"We're delighted to get Kane in. He brings a lot of athleticism and quality to the team, alongside experience in League Two," Rochdale boss Ian Watson told the club website.