Many have body refining parts, it tends to be the first step for cultivators. Martial World (big part of current translation) True Martial World Ancient Strengthening Technique
Stellar Transformation. It has a unique form of cultivation. Well then MC have it. The LN is also completed. Chaotic lightning I think that's the title. Anyway, just look at the tags. And you'll know everything.
To name a few: Against the Gods Mythical tyrant Chaotic Lightning Cultivation Desolate Era Also you could just click on the body refining or unique cultivation tag to find some novels.
The Tales of the Reincarnated Lord has a unique cultivation. And also Transcending Through the Nine Heavens.
TNC Desolate Era World of Cultivation (not body strengthening per se. More like body restructuring) Martial world (especially current arc)
Emperor's Domination. It has unique body refining(since most notable characters refine their body instead of just the MC) and every character has 3 separate cultivation techniques.
MC's the only one training his body while everyone else trains their inner strength(like qi) The Nine Cauldrons