Show self-hosted mp4 and mp4 videos and audios (post types) in the home page grid in Pluto theme -- 2

Presently the Pluto wordpress theme supports only youtube videos and soundcloud audios to be embedded in the home page masonary grid thumbnails. It gives an url field when we choose video or audio as a custom type in the add new post page. But it gives a blank thumbnail when we put a direct mp4 or mp3 link in that custom url. I want it to support mp4 and mp3 url links. I have some videos which are recorded in portrait on a phone and I want them to be shown on the thumbnails in portrait in a playable manner in a html5 video player and also a smaller player for a mp3 audio. Work in child theme please. Pluto theme demo: [login to view URL] Pluto theme details: [login to view URL] There is no demo on the video and audio embed on their demo site but I can show you on my site if you want. Please write how you will do this in your bid instead of all general stuff.