The short version: you can’t.
Longer version: To do what you’re asking requires that you write your struct using templates which would allow you to do something like TArray< FMyStruct< int > >. You can do this but with the limitation that it can’t be a UPROPERTY.
Unreal’s reflection support is very limited when it comes to templates. Not even the TOptional template provided by the engine is supported as a UPROPERTY. The containers (TMap, TSet, TArray) are the exceptions and have special support to enable them.
Even so, the support for them is limited and TArray< TArray< int > > isn’t supported as a UPROPERTY (which may have driven you to the struct wrapper, a common Unreal idiom to get around this restriction).