At least some of them should. I’m not sure which accessories you’re talking about, but I know I use the FM transmitter I bought for my iPod when I want to play music on my iPhone through my car speakers.
I can also use the chargers I had for my iPod for my iPhone.
Things like cases may or may not work. Some might fit, but not fit as well. Silicone/fitted cases probably wouldn’t work.
Hope this helps! :)