of course you can. they just won't get it before they come online. which is kind of duh! for instant messaging, isn't it?
now, if you're concerned about the two of us never being online at the same time, install Jami on your home server, or on a VPS, link your account there, and it will get a copy of your messages whenever you send or receive them, and it will transfer them to your peers or to your own device whenever they come online.
now, if that's not good enough for you, I guess you really prefer to share your conversations with third parties for them to do this for you. me, I prefer my autonomy.
CC: @davep@infosec.exchange @rysiek@mstdn.social