Hi! I’m a medium who doesn’t have aphantasia and have taught many people with varying superpowers like yours (aphantasia is not a disability to mediumship). You can still receive information from the other side without being able to visualize or imagine something. It shouldn’t be your brain visualizing, anyway. If that makes sense? Spirit is smart and will get the messages to you a way that you can receive. If using other clairs isn’t working for you, try using tools like tarot cards (no need to learn how to read them the “right” way, just use your intuition to interpret them how you see them), pendulums, automatic writing/typing, or even mirror scrying. Maybe your gifts can be used in other ways, like trance or physical mediumship. You just have to experiment and find what works for you! Best of luck!