What is the green, rectangular object?

install some trellis' on the fence and encourage some flowering vines.

How much sun does it get?

if the green box could be utilized for temporary seating,

clean up and level off the area and Re install pavers.

The green object is a utility box.

Remove the pavers and add shrubs. I'd go with broadleaf evergreens, like mt. laurel.

What function do you want the corner to perform? Do you want a seating area? I would remove everything there, including the angular edging. If you want a seating area, lay paving correctly, ie level and firm. Make the whole space larger with a smooth natural curved shape. Don’t edge it unless you can do it to a professional finish. Otherwise just do a clean cut slit edge to the lawn. Choosing plants is the last thing on the to do list. The bones need to be right first.

I would remove EVERYTHING but the utility box. And then plant hedging to obscure it. I would not focus any attention on it. Instead, I would move your seating area away from this corner.

Don’t make the utility box a focal point. Have your planters and seating area elsewhere.

I agree but it would be nice to see that whole area from further back .

Surround the utility box with grass instead of decorating around it.

Pick up all the yard decor, the roof shingles, the pavers, and the edging. Put the yard decor up on a table to see what needs cleaning or painting. Give away the things you don't love (a "free" pile out front may work in your area). Then plant your planters and pots with fresh colorful annual flowers in a new location such as a place you can see from your kitchen window.

Apple Pie mentioned one of my favorite garden mantras so I think it bears repeating:

Plant something lovely where you can see it from the window.

At my last house, I had a back yard that gradually ascended a small rise. So I sat on my favorite corner of the couch, looked out the sliding glass doors, and planted a shade garden with hostas, etc RIGHT THERE where I could see it. It was awesome. 🌸🌱❤️

Utility boxes /transformers are in the utility owners right of way easement and usually landscaping etc. will be damaged if work or replacement (hoisting in a new transformer) take place in that area. Just be aware that these boxes must be accessible and the utility company will not take responsibility for damages entering or even exiting your yard or even destruction of hardscape in that particular area.