Hi Alan, welcome to Hive! Hive split off from Steem on the 20th of March, so it makes sense that your Steem posts after that date don't appear here.

Copying those posts would be fine, especially since it's a handful of posts about timeless topics. Edit: your posts might be labeled as plagiarism by Hive account@cheetah, though. Which wouldn't hurt you directly, unless Hive account@steemcleaners start downvoting. I'm sure they'll listen to your explanation.

Since this a new start, both for you and the blockchain, you could also introduce yourself again using the #introduceyourself tag.