Arsenal striker Eddie Nketiah appears to be edging towards the exit door this summer, amid links to several centre-forwards. However, his replacement may not necessarily be a new addition, but an internal solution in youngster Mika Biereth. Biereth has excelled out on loan this season, at Scottish side Motherwell and now Austrian title challengers Sturm Graz, with the 21-year-old following the path of Manchester United forward Rasmus Hojlund. Nketiah could move within the Premier League for a fairly significant fee, and several strikers including Viktor Gyokeres and Ivan Toney have been linked…