Is a Thai marriage visa eligible for a yearly tax return if I work in Thailand?

You are still required to pay taxes in Thailand if you work for a Thai company. They will with-hold your taxes on each pay check. Sometime in late January or early February they will give you a tax form for the year. You will take this to any revenue department and they will figure your actual tax amount. You may get a small refund, or you may owe money. There is no way of knowing this till you go. Amd taxes have to be filled every year to renew your work permit.

Why do you want a tax return?

Normally if you work in Thailand tax will be withheld from your salary by the company you work for but that doesn't rule you out from doing a tax return if you have a reason to

Tax return is related to tax taken out of your paycheck from your job. It’s not related to your type of visa.

Being on a working visa or marriage visa has nothing to do with your taxes.