Xvid is an open-source video codec library following the MPEG-4 video coding standard, specifically MPEG-4 Part 2 Advanced Simple Profile (ASP). This codec was created as a free alternative to paid MPEG-4 and DivX codecs.

Xvid codec is available in Movavi Video Converter as read-only, so you can convert your original files encoded with it into other formats.
However, it's not available for output videos, because Video Converter already has proprietary MPEG-4 codec included.

Audio Video Interleave (.avi)Read / WriteH.264, MPEG-4, MJPEG
Read OnlyDivX, Xvid, DV, Cinepack, Fraps, TechSmith, No Codec

This is a part of the table which shows all supported formats and codecs of Movavi Video Converter. You can see the full table here.

A large number of the divX/Xvid-compatible devices support AVI encoded with MPEG-4 codec. 

In order to produce videos for devices which require Xvid codec, you can try selecting the AVI format with MPEG-4 codec for output.
Same applies to DivX codec.

If you would like to use the product for a specific device, we recommend checking out the trial version of the application first to see if the output format is compatible with your device.