So I think your art is good, but when it comes to commissions, a lot of people aren't creative enough to see that you have the potential to draw what they want unless that is exactly in your portfolio. My teacher once said he nearly didn't get a job for painting a boat solely because while he had vehicles in his portfolio--there was no boats in it. That's how literal not-art people are.
So like people freakin love sonic and fanart (and these look great), but they probably don't need a commission of sonic. What will be the ideal commission that you want to make for your potential client? A portrait of them or a friend? (like the picture of the girl on a bench is solid for a commission example) A picture of a DnD character? A picture of their pet maybe? Like brainstorm what you want to get hired for, and draw some of that for your commission ads, and that will help draw in more of the work you want.
And in the mean time (because it is slow to get commissions sometimes) you can always sell prints that are really marketable (and doing a print-on-demand is a good way to test the waters without spending money on printing), so home-goods, stationary, immersive landscapes, stuff your ideal client would put on a wall. Again--can't really use fanart for this, fanart is more for getting traction on social media--but a lot of illustration is figuring out the needs of the market, and making it available for them, because people just aren't that creative.
