Though it might be too obvious, I actually really like MetalGreymon (Virus) X as a jogress between Gizmon AT and Greymon X. It has the purple color scheme and tech from Giz’ and the body type and antibody from Greymon.
Gigadramon would also be a possibility if one wanted to go with a less obvious route (also with Gizmon AT’s color and tech with draconic elements from Greymon X).
For Hippogryphomon + Triceramon, I chose Dorbickmon (Darkness Mode Dragon Army). His back looks like a mutated Triceratops, as a fusion he’s like a chimera and has a fiery attribute.
For the Shitori game jogresses:
Tsukaimon + ToyAgumon = Tobucatmon (flying toy)
Gossipmon + Liamon = 2 choices here. A dominant Gossipmon can result in Assaultmon (a fierce centaur). A dominant Liamon can result in Oujamon (a multi-limbed lion cyborg Appmon).
Algomon + Beetlemon = GrandisKuwagamon (insect humanoid with dark coloration)
Aegisdramon + Blastmon = MoonMilleniummon (extremely powerful chimerical dragonoid encased in crystal)
Devimon + Ankylomon = evil Shakkoumon probably DarkKnightmon, maybe SuperDarkKnightmon (to combine the armored aspect with a darker nature)… or Infermon to be more bestial, though no longer as good an antithesis to Shakkoumon.