Actually, the action on the MSX could use a static screen for most battles ...
In fact since the MSX2 has four video pages, it could use a sprite mask on the boarders and set adjust to simulate a scroll on a 240 (or less) pixels on Screen 5.
Disabling the sprite mask on the borders for fixed action. Dropping a enemy or two on the view port of the screen.
If someone do not care (MUCH) about locked action on the screen, it would be feasible on standard MSX2 Home Computers ... One player and two enemies is not much by the MSX-Video standards!!!
I always thought that of R-Type.
While the MSX1 version is very decent IMHO.
A dedicated port for MSX2/2+.
Probably it could be so good as Space Manbow or "Manbow 2".
I first trough that the R-Type was intended to be used on MSX2 computers, but the (ORIGINAL) cartridge seems to work in plain MSX computers equipped with a FM-PAC ... One of the few MSX1 games to support external cartridges !!!