Libreelec as wifi hotspot?

Yes. Not sure whether the recent samba changes might cause issues in the latest (8.2 and onwards) versions, but I use pi's in my car like that - play music / audiobooks via the car stereo controlled by yatse, watch videos (or rather mostly others do) on android tabs via smb. I connect a bunch of (independently powered) portable drives to the pi for video on long trips, music is on a usb stick.