Elements may be sufficient for your needs. In order to make a digital negative, you will need layers, curve adjustments and color adjustments. Basically you will take your scanned negative, turn it into a positive image, perfect your image (burn, dodge, crop, etc.), apply an adjustment curve, turn it back into a negative, add a blocking color and then print it out on a piece of transparent film on your photo printer. If Photoshop elements can do all that, you don't need much else to get started. If you like it, you can upgrade later.
While this sounds direct, you will need some basic training in photoshop. This training can come from a local tech school or community college. Photoshop is very challenging to learn on your own.