I haven't seen the one piece films with the exception of Stamped and Gold but I think there are some films that are not suitable to put as Canon, as for Shiki's film if I remember correctly Luffy uses 3 gear and Haki if you go add will have to make some changes to make it believable why Shiki was so weak. (canon says he gets weak after taking a beating and running away from impel down but still Luffy had to fight seriously to defeat him, so you'll need to explain how he lost)