Will an unlocked Pixel 4a work on PagePlus?

I’m thinking of buying from Amazon an unlocked version of the Google Pixel 4a for use on PagePlus.

Will PagePlus activate an unlocked version of this device?

Do carrier-branded versions of this device exist, or is every Pixel 4a sold in the USA unlocked?

I’d prefer not to buy a Tracfone-branded version of the device (if such a thing exists), in case I want to change carriers in the future.