As of my last update in January 2022, I can provide information on the Hyundai Sonata up to that point, but I don't have access to real-time data for future models like the 2023 Hyundai Sonata SEL. However, based on historical trends and features commonly found in mid-range trim levels, here's what you might expect from the 2023 Hyundai Sonata SEL:

1. **Engine and Performance**: The 2023 Sonata SEL could likely come equipped with a choice of engines, possibly including a base 2.5-liter four-cylinder engine or an optional turbocharged 1.6-liter four-cylinder engine. These engines would offer a balance of performance and fuel efficiency.

2. **Transmission**: Expect a modern automatic transmission, possibly an eight-speed automatic, to accompany the engine choices for smooth shifting and optimal efficiency.

3. **Interior Comfort and Convenience**: The SEL trim typically offers a range of comfort and convenience features. This could include amenities such as heated front seats, dual-zone automatic climate control, a power-adjustable driver's seat, keyless entry and ignition, and a larger touchscreen infotainment system with smartphone integration (Apple CarPlay and Android Auto).

4. **Safety Features**: Hyundai places a strong emphasis on safety, so the 2023 Sonata SEL would likely come standard with advanced safety features. This could include a suite of driver-assistance technologies such as forward collision warning, automatic emergency braking, blind-spot monitoring, rear cross-traffic alert, lane-keeping assist, and adaptive cruise control.

5. **Exterior Styling**: Expect the SEL trim to feature stylish exterior elements, possibly including alloy wheels, LED daytime running lights, and chrome accents.

6. **Space and Practicality**: The Sonata is known for its spacious interior, offering ample room for passengers in both the front and rear seats. The trunk space is also typically generous for the midsize sedan segment.

7. **Optional Packages and Upgrades**: Hyundai often offers various optional packages and standalone upgrades that allow buyers to further customize their Sonata. These could include features like a panoramic sunroof, upgraded sound system, leather upholstery, and advanced driver-assistance features.

For the most accurate and up-to-date information on the 2023 Hyundai Sonata SEL, I recommend checking with Hyundai's official website or contacting a Hyundai dealership closer to the release date.