The story that Schleich flew an all-black triplane is unfortunately a myth, engendered by J I T "Taffy" Jones' books. On 12 April 1918, on his first fighter combat patrol with 74 Squadron, Jones narrowly escaped from an all-black Triplane; we now know this was actually Josef Jacobs of Jasta 7 (the description in Jacobs' diary, time, places,..everything matches). However, during the 1930's Taffy met von Schleich at least once and became somehow convinced that it was von Schleich he tangled with that day, and said so in his various books. I imagine the two old aces overlooked the niceties of time, location, and even aircraft type - or else this was lost somehow in the translation between them. At any rate, Schleich had indeed flown black aircraft, so it seemed a good match to Taffy.
As for Schleich's actual aircraft, might I be so immodest
as to suggest you check out my article on this ace's aircraft in "Over the Front", Volume 13 No. 3 ? In his very early days Schleich was photographed in front of a very plain Albatros C.I. He also flew a well-known Roland C.II "Walfisch", either at Schutzstaffel 28b or, perhaps more likely, at Flieger Abteilung 2b. There are photos of this plane in the Roland C.II Profile and Datafile, and one on page 208 of the recent C & C International Journal, Viol. 32 No. 4, 2001. After he took command of Jasta 21, he flew the very familiar Albatros D.V with his own Bavarian lion emblem on a circular field of the Bavarian crest pattern of blue/white diamonds.This machine also bore the black/white fuselage band of Prussian Jasta 21, and standard camouflage on wings and tailplane. This aircraft has been illustrated many times, once in the Albatros D.V "Profile", but be aware that the lion emblem faced forward on BOTH sides of the aircraft. On 27 July 1917, Schleich lost his good friend and J. 21 pilot Erich Limpert, and he reportedly had this same Albatros D.V painted black in mourning. From then on he would be associated with black aircraft (but never flew a Dr.I, as far as I know !).
As commander of Jasta 32b he flew an Albatros D.V which had a black fuselage and tail, with a white spinner - it's possible the wings were black too. When he commanded Jagdgruppe 8b he flew an Albatros D.Va with all-black fuselage, undercarriage, wheel covers and tail. This machine had five-colour fabric wings and the early style of Balkenkreuze. This D.Va had formerly been flown by Kissenberth, and the photos show traces of the former pilot's edelweiss emblem beneath the black overpaint. You can find a photo and color profile of this D.Va in the Osprey Albatros Aces book.
In late 1918 it seems Schleich flew a Fokker D.VII (OAW) but all we have to go on for this aircraft are two of Rudolf Stark's paintings. The aircraft probably had an all-black fuselage and tailplane, with white fin/rudder and four-color lozenge fabric wings. It bore Schleich's old Bavarian lion insignia, again on a circular design of blue/white diamonds, and also had two blue and white streamers trailing from the interplane struts. A color profile of this a/c appeared in "Fokker D.VII Anthology 2" from Albatros Productions, but we goofed and Ray Rimell's painting shows the lion facing the wrong direction !
As for Ltn. Walter von Bülow-Bothkamp, there are not many photos of his aircraft available. While he was in Jasta 18 in 1917, he flew Albatros D.III 1954/16. This machine had a plain varnished fuselage, with a very dark(probably red or black) thin vertical stripe aft of the cockpit and dark wheel covers. There is a captioned photo on page 42 of Alex Imrie's "German Fighter Units 1914-May 1917" (Osprey /Airwar 13, 1978). There is anothe photo on the back cover of C & C Journal (US) Vol. 12, No. 3, 1971. I have no information on aircraft flown by von Bülow in other units.
Hope that is of interest,