I received an insulated wine cup made by ice shaker- I just looked it up on Amazon and it’s $18.50 and comes in cute colors. I have the pink one.
I knew I was coming to the right place. You all are awesome…so many good ideas! Now to figure out which way to go… 
I will report back later in the week with what I end up with (and what other gifts were too). Thank you all!
I’m with you @thumperr , a gift card would be more appealing to me too in this instance -coffee/tea shop, movie theater, etc. Maybe something consumable.
Yes, gift cards and cash are popular in our “swaps.”
Solar powered cell phone charger. There are some 0n Amazon for under $20
Charles Viancin silicone bowl covers. They really work and come in different flowers (different sizes). Mine is a 10 inch round (covers my salad bowl perfectly so gets used a lot). They make a rectangle one to cover casseroles now also. At Amazon and BBB (use a coupon!).
OP mentioned in her first post rules were no food, no gift cards.
@gouf78 +1 on those lids.
Uh-oh! My mind’s in the gutter.
Did someone mention battery-powered . . . . . . .???
Costco here (tx) had a lovely rosemary plant shaped like a like a mini xmas tree and under 20. It was lovely and they were very popular. It was a jolly good size for an actual rosemary plant and they looked healthy.
We got one of those rosemary plants one year but the smell was overpowering in the house.
I wish we had Costco…I love the smell of rosemary.
I saw something on Facebook from Costco about gift swap ideas. Look at this article and scroll down to the second suggestion - https://www.costco.com/my-life-gift-exchange-ideas.html?SOCID=Facebook_Posts_LIST_IdeaGiftExchange_1129_FY19&fbclid=IwAR3OdZ6eEHVseprPeZvotMXxniqpk5W23uL0QlzVinxFNgNUzIpwP6Vy4Oc
All of the fillable ornaments I’ve seen are clear plastic, though, so you’d have to disguise the cash somehow – maybe inside some crinkled red tissue paper. I’d think someone would be pretty pleased to get a $20 bill along with a reusable ornament! 
Taping cash to the bottom of a potted plant is generally pretty popular too.
An assortment of quality tea bags is always welcome in our house.
Some can be a bit pricey, but there are many to choose from on Amazon.
I just ordered this for my daughter who is a college freshman.
https://www.amazon.com/gp/product/B000S6CCJ8/ref=oh_aui_detailpage_o06_s00?ie=UTF8&th=1
She was so excited and loved the box.
It is great for personal use and when guests come over.
Peeps glasses cleaners.
https://www.thegrommet.com/peeps-carbon-eyeglass-cleaner
Scented anything is out in my house - candles, tea, Rosemary, diffusers
How much is a Squatty Potty? I’m sure that would be an interesting gift swap item.
^^^And you can use your $5/20% off coupon!