Hi Christy,
If you want a flexible, clear resin, you will want to use a clear silicone resin. You can embed your items in a formula like that.
To make a wine glass sleeve, you will need to make a template, then mold it. Once you’ve got a mold, you can use a silicone resin to make the wine glass holder.
This article gives more help on how to make the model for your mold: https://resinobsession.com/resin-frequently-asked-questions/selecting-a-model-for-your-mold/