I have gotten a external capture card (ezcap Cam Link 4K) to stream games from my consoles, but when using my PlayStation with it, it gets blocked by HDCP. I've tried an HDMI splitter and look up other ways but they all don't seem to work. Is there a way around this issue or am I screwed?

this depends on the playstation. on playstation 3 you need an hdcp stripper (i personally use component so i sadly cant say which splitter you should get). on playstation 4 you can turn it off in the settings. and on playstation 5 i assume you can also turn it off.