How Do I Whitelist Bedrock Users on a Java server?

[NinjaTiger58]

I have some friends and family who currently can't play on Java Edition, but my server is whitelisted and I need to add their Xbox usernames.  I know that you can't join on an actual Xbox, but they can play using Minecraft for Windows. So far, my results have either been that the player doesn't exist or an error. 

[linkinpaws]

put a period (.) before typing their username.

[DuckyProgrammer]

You can't whitelist bedrock users unless they join the server first.