Some people might think it's not a big deal to see your sent pictures on whatsapp. You can do that by opening the WhatsApp >> then choose the person >> go to the top and click on the person's name >> and click on the Media.
Well, you are right and I really like the way WhatsApp organises all the sent and received pictures, and you can see which picture has been sent to which guy, but I didn't find any option to copy any picture or video. So this post will be about how you can get to the WhatsApp's sent picture folder and see where those pictures are saved.
There are two option you can choose from.
Option 1, short cut way:
Go to My Files >> click on the search box at the top and search and type sent then click search >> now you will see lots of sent folders, just start with the top one. Hopefully that will be the WhatsApp's sent picture folder. If that was different one on your mobile then go back and try another one.
Option 2, long way:
Go to My Files >> Device storage >> WhatsApp >> Media >> WhatsApp Images >> Remember in this folder you will find all the images you've received then at the bottom you will find a folder called Sent in that folder you will find all the images that you have sent.
And now you can see some of your old pictures that you have send to someone and have some laughs. :)
This is for Android phones only I'm not sure about other phone.