These toys were bought sometime in the 90s at various garage sales or flea markets, and I just dug them out of storage. But I haven't been able to find much about them online. Alt modes in the first image, robot modes in the second.
1. This vehicle has the markings "©1989 Hasbro inc" "©1989 Takara" and "Macau". The armor locks in place in the back, and when a button is pressed, it flips forward over the cockpit, though there is a place on the top that may have held rotors. Looks to fit G.I. Joe: Real American Hero sized figures.
2. Transforming space shuttle. The hull of the shuttle is egg-shaped, and has fold-out landing gear. It also has die cast parts. There is a small, non-removable, chrome astronaut in the cockpit. Markings: "Taiwan 1984" and "© G.K"
3. A knock-off Powerdasher? Stickers on the legs say "Dynamic Robot". "Made in China" on its back. Any details on this (even if it's a KO) would be great.
4. This piece is obviously broken and missing pieces. Looks like it probably had arms. Makes me think of Robotech. No markings.
5. Mazinger? I know nothing about Mazinger, other than the general appearance of the robot. I always liked this little guy, so any specifics about it would be fantastic. "Japan" on its back.
6. Nothing special about this one, except when rolled forward sparks would fly out of its mouth, and sparks were visible through the three red windows on its back. Markings: "Supreme" and "No. 222" in one of the wheel wells on the bottom.