Definitely! Dragon flags and HLR are both excellent abdominal exercises that help you prep for the front lever. But dragon flags should be harder, what do you have against HLR? If you find the dragon flag to be easier, you likely are piking your hips during the movement, which is to be avoided. But if you simply prefer the harder exercise then more power to you!
@robby: I can’t do dragon flags. I am doing negatives and one leg in variations. I am trying to build upto full dragon flags. I can not resist the swing in hlrs. I do pull ups with towels. Towels are certainly not a good equipment for hlrs. Thats why I do modified dragon flags. Plus I enjoy them way more than hlrs.
I’d suggest not using towels for HLR, just hang from the bar. You can resist the swing if you go more slowly. This control starts at the upper body, actively “push” the bar forward and down while focusing on the speed that your hips are moving, while also keeping your back and abs rigid.
For more abdominal work, I suggest working on building up time on L sits and also doing L pull ups. L towel pull ups are quite challenging!