Depends on what you buy. I’d suggest not buying an enshittifiable IoT device but something you can control with a microcontroller like ESP32, such as displays that got decommissioned from train stations. You’ll likely have to write code to generate the driving pulses along with making the Pixelfed API calls. Some companies might be still making ones that can be controlled via RS-232 or RS-485, which would be very easy to write code for.