Limited Capability to Work & Self Employment

I was deemed limited capability to work last year, so don't have to look for work to keep getting universal credit. I've been pursuing a freelance writing career and want to be self employed at some point, and though I've now just started to make some money, it is not enough to live off yet. I've had a mare trying to declare some earnings and I don't meet the criteria to register as self employed and there's this;
"If you cannot show all these things, you might have to look for other work if you want to keep getting Universal Credit."
Because I'm deemed limited capacity to work, does anyone know if I'm able to register as self employed but due to being limited capacity, I don't have to look for additional work to continue to get universal credit? (Even if it's I don't get limited capacity payment but I still get universal credit, I can only write because I can work from home and manage my needs)