Do you like both strands?
Would you wear both strands at the same time, because they match?
I have several blue akoya strands, and yes they are the same type of pearl, but I can pretend one strand is Tahitian for the moment. I love wearing them all together.
But, if you feel like you have two strand that seem like twins, and you won't wear them together, then either send the new one back, or sell the old one.
I don't believe the that pearls accumulate energy from around them. I think that people develop attachments to certain pearls because of their history with those pearls, but the pearls themselves doesn't know that. I personally find it hard to get rid of any of my pearls, even the ones I don't wear, or are worn out, because each piece reminds me of someone in my family. However, once I sell the first piece, it will be easy as pie to sell others I don't wear. I know this is true for me, because it happened with my looms. Believe me, looms take up way more room than pearls, and I just couldn't part with them. Then I finally decided to sell them all and buy new ones that consolidated all the various features, and once I did, I was much happier. Where was I going with this? Oh, do what your gut tells you to as far as keeping both or getting rid of one of them.