The videos are already on a USB stick I heard getting one of these and connecting to it locally is more secure than just plugging the USB stick into a ISP branded router.
I am looking at the GL.iNET portable routers on Amazon AU which seem to have good reviews.
https://www.amazon.com.au/GL-iNet-GL-MT300N-V2-Repeater-Perf…
https://www.amazon.com.au/GL-iNet-GL-AR750-300Mbps-pre-Insta…
I remembered the old product called RAVpower Filehub which serves a similar purpose, but that had a built in battery which is not needed. The GL.iNET ones are perfect since they are powered by USB.
It's for my elderly mother so she can access all her DVD's I ripped years ago from her tablet using the VLC player app.
Anyone have any experience with either the GL.iNET GL-MT300N V2 or GL-AR750? Will the 750 have better WiFi range for $13 more (after coupon) even though both models use internal antennae?
If your router has local file sharing, just do that. It's secure enough.
Edit: Just to add some more information so it doesn't look like I'm not being helpful. If you purchased a device like you are suggesting, it would mean your gran would have to connect to a different wifi network each time she wants to watch her videos. Is she going to know how to switch between networks all the time?
Honestly, security isn't really a concern here. You're better off changing her SSID and wireless password from default than purchasing any extra hardware like that.