I would like to know if the SIM card I currently have in my Moto G5 Plus will work with a Google Pixel 4a (Manufacturer’s Part Number (MPN): GA02099-US)?
There are multiple types of SIM cards. If yours is GSM, it can be moved to your new phone. If it is not GSM, open a Help Ticket for a replacement SIM card.
I just did this successfully. I bought a Pixel 4a from Amazon a couple of days ago, because Republic was out of stock. Just took the RW SIM card from my Moto G5 Plus, put it in the Pixel and everything works as expected.