When we moved into our place in 2016,there were the standard old person low maintenance shrubs and bulb flowers all over the place. My wife is a wildflower nerd and works for forestry as an educator, so she took the reigns on converting some of our garden beds to native pollinator gardens.
This thread has a list of many of the choices we made.
I also planted a male pussy willow (Salix discolor) for early blooms. It is one of the first natives to wake up to help the bees and you can easily train in as a large shrub. Dead easy to root from cuttings, literally cut a branch and stick it in the ground, preferably in the spring or fall. I could take some cuttings if you are interested, I already pruned ours like crazy a couple weeks ago but I could find a branch to trim.
Locust is another great pollen source, a tough tree, and can be used for very slow rotting fence posts or other garden projects if you coppice it regularly.
Honeyberries are super early bloomers too, possibly TOO early for my native pollinators to wake up. I haven’t tested that theory yet but have a bunch ordered.