Order of cleaning agents for kegs

If you wish to clean your liquid out lines with keg line cleaner, should the order be (1) PBW, draft line cleaner, then star san as final or  (2) PBW star san, and then draft line cleaner?  Thanks in advance for your advice?

I would do Star San last. You need to flush your lines when using Beer line cleaner.

Star San is a sanitizer, not a cleaner so it does no good to use it first. You cannot sanitize what isn’t yet clean.

Although sanitizing beer lines is not a bad idea, I don’t do it.  I use caustic (beer line cleaner, aka BLC, is the same thing) in hot water and pump it through the lines three times, letting it sit in the lines for about 5 minutes before pumping a fresh charge of caustic into them.  Caustic/BLC will kill anything organic and also eliminate the need to also use PBW.  Caustic and BLC contain sodium hydroxide and also have surfactant cleaners in it to remove any accumulated soils from the lines, making PBW redundant IMHO.  On every other cleaning, I take the faucets apart and clean the internal parts just to be safe.  The caustic does a really good job on them, but I like to inspect them occasionally for things like beer stone.  If I see that then I use an acid wash after the caustic cycle. Star San will work for that (because it is an acid) although a commercial acid cleaner (available from dairy supply stores) is much better.
I then flush the lines with hot water three times and am done.  I have never experienced an off flavor from using this method. It also saves me time and money.
That said, if you want to clean your lines in the way you mentioned, use the Star San last.

Cleaner always come before sanitizer. When I clean my lines I do PBW > flush > BLC > flush > Star San, although the PBW probably isn’t needed with the BLC. Between kegs I just flush the lines with Star San.

I just use hot water, BLC, hot water, Star San, beer after every keg. I feel like there are a lot of extra steps here. I clean the kegs separately, though. Water, PBW, water, Star San. I take apart the faucets after every keg, also.