Arsenal will kick off their Premier League title defence next weekend against newly promoted Coventry City without William Saliba. The France centre-back faces a lengthy spell out after injuring his back at the World Cup. Jurrien Timber, who missed two months late last season with an ankle issue, is also a doubt for the opener.
Liverpool retain a matching clause for Quansah following his move to the Bundesliga last year, but they are not expected to activate it.
Quansah was in the England squad that made the World Cup semi-finals this summer. He started three matches at right-back but was sent off in the last 16 against Mexico, which ruled him out of the quarter-final win over Norway and the semi-final loss to Argentina. He made 44 appearances for Leverkusen last season, scoring five times.