Basics: 486SX no mathco, DX has mathco, DX2 runs 2x internally, SL is Low power version, WB and WT are cache schemes.....
the 486 DE2 chips are AMD's 3.3v DX2's, if the board supports 3.3v cpu's you can use one, set same as a AMD DX2 but 3.3v instead of 5v.
387sx is mathco for 386sx, 387dx is mathco for 386dx. someone else can go thru the other 386's 🤣

The 386dx has a 32 bit data bus while 386sx has a 16 bit data bus which means the sx needs twice as many memory fetches to get the same amount of data from memory which reduces performance significantly. This is similar to the 8086 and 8088 which differ by the width of the data bus but are otherwise identical. I belive the 386sx allowed board manufactures to use 286 chipsets which reduced cost significantly

Define "normal board"

All 486 boards support 5 volt cpu's (so, you could call this "normal"), the ones made halfway through the era usually support 3.3-3.5 ish. In which case no, you couldn't run a DE2 in every motherboard.

what is the difference from Cyrix 486 80 and v80? v80 has 4v 3.45v 3.3v version，what is the difference? is it because of procedure?0.8 0.6um?