since item frame are not entity , it's not possible to replace the item with /replaceitem entity

and it's not possible to use /replaceitem block either to replace the items inside the item frame

note: in the java edition the game count the item frame as an entity which allow players to place a button and an item frame in the same block 

In the bedrock edition the game does not count item frame as an entity, so in any commands for example /kill @e[type=item_frame] the the command wont work. Also you cannot put a button and an item frame in the same block because item frame as counted as a block

also the item frame is not counted as a container like chest and furnace, because of that you cannot use /replaceitem block

/replaceitem block to put an item in the item frame