How to trim vinyl flooring around fireplace hearth?

There are mouldings available to match the color of your flooring. Check with a flooring store to get what you require to finish the job professionally.

Have you thought of building up the hearth. I attached a picture of a renovation that I’m working on. It will just give a little definition and separation of the area. The previous home owner had quarter round around the base of the bricks. I’m going to put quarter round in the color of the flooring around the fireplace. Just a thought.

You would need to install a transition molding overlapping the flooring and brick.

https://www.homedepot.com/b/Flooring-Hardwood-Flooring-Wood-Moulding-Trim/T-Moulding/N-5yc1vZaq8oZ1z0z6ge

https://www.youtube.com/watch?v=gyjLA0iBdPQ

Try some quarter round, lowes has several different options. Take a piece of the flooring with you to match the color

Is the fireplace for show only or do you intend to burn in it? In our area, the fire code specifies three feet of non-combustible material (such as brick, tiles etc.) in front of a working fireplace or woodstove. Might be worth a check :-)

Our fireplace is granite and when we had our flooring installed the installer did a great job cutting the flooring and using a a silicone caulking in a color almost a match to the flooring.

You can buy what's called transition molding/t-moldings it comes in all sizes,shapes,metal or wood and also used in doorways or anywhere you are using 2 types of flooring here's examples https://www.google.com/search?q=flooring+molding+for+different+heights&rlz=1C1CHBF_enUS750US750&tbm=isch&source=iu&ictx=1&fir=mAIOywwxGeaCHM%253A%252CL1rZr_uEmheWZM%252C_&usg=AI4_-kR4lb2_FzlHqVpBRe2M-sKtMnrCAg&sa=X&ved=2ahUKEwjfzpu87-_eAhUBwMQHHWgEBl4Q9QEwE3oECAIQDg#imgrc=mAIOywwxGeaCHM:

The company that made your flooring most likely has a transition piece that is designed to end your flooring. If not you can find someting close in color from one of the other mfgs.

JMO. The hearth being lower than the floor will call attention to the fact that a new floor was added. An original hearth would be even with or higher than the floor. In this case I would add a new hearth. I think a one piece slab would look good. Slate ,Bluestone, Soapstone. Concrete would work with a faux finish. If you prefer brick you could use thin brick veneer or and add another layer to the existing heart.

Also that plain white plaster around the brick opening looks off to me. A Craftsman fireplace would have had a full wood mantel and or fancy tile work. The tile work often was continued on the hearth.

https://www.pinterest.com/losthilllady/craftsman-fireplace-ideas/?lp=true

If this is a working fireplace check first before raising the hearth too much.

You will need something in front of the fire area, probably tile. Then you can transition to the wood with either shoe molding or quarter round stained to match the wood flooring.