HSBC US (NYSE Listing) is an ADR => underlying are 5 shares of HSBC's London listing (HSBA LN).
HSBC has numerous listings around the world (313 according to Bloomberg), and HBCYF (OTC) is one of them. Unless you have a particular reason to look at a specific listing (reasons could be related to market access, arbitrage etc - but you would not have to ask), you are probably best off sticking to the most active listing you have access to. For US investors this is HSBC US (~3.6mln shares daily volume). This compares to only ~22.5k shares for HSBCYF.
Note that the ADR are not the most active shares traded worldwide: The bank's HK shares (5 HK) have an avg. daily volume of ~42mln shares while the UK listing (HSBA LN) has an avg. daily volume of ~24mln shares.
Hope this helps