The Multi-Tasker 4-in-1 Makeup Brush by Alleyoop is highly recommended by Meryem in their video review. Meryem expresses excitement about this versatile brush, which can be used for blush, contour, concealer, eyeshadow, and even eyebrows. They particularly love the softness of the brush and appreciate its compact design, making it perfect for on-the-go touch-ups. Meryem rates the product 10 out of 10 and recommends it to others. Overall, the Multi-Tasker 4-in-1 Makeup Brush seems to be a must-have cosmetic tool, offering convenience and versatility for various makeup applications.