You can develop voicebanks for Deepvocal, Vocalsharp, Myriad Virtual Singer, which is older and more robotic, but supports most voicebank types, and Renoid Player, which requires the program Renoise and a CV Japanese voicebank. You can also create voicebanks for amateurishly made vocal synthesizers, which you can find on some kids coding websites or coding playgrounds, and create Elevenlabs AI voices, which are similar to Coieroink, except can speak more languages. However, you must pay money to make an Elevenlabs voice to my knowledge.