The 25-year old made represented Dulwich Hamlet last season and previously spent a successful two-season spell with Oxford City, playing a key part on their National League South promotion-winning campaign in 2022/23, before making 31 appearances in the National League in 2023/24.
In total, Williams-Bushell made 76 appearances for Oxford, scoring three times.
After a number of impressive performances for the Wings during pre-season, Lee Martin added him to his squad ahead of the start of the 2025/26 campaign.