Two appliances with connection cords sharing power outlet
Many of these cords are made this way to reduce the stress on the wires inside caused by having the appliances then shoved up against them. There are many cords available which are not made with the 90 degree angle. You just have to go to your store and find them.

Here's an example of one from Amazon:


They have dishwasher cords similar to this too. Keep in mind that dishwashers need to have GFCI protection so you might want to add a two gang box and have two outlets, which would allow you to use the cords you originally wanted to. Good luck.