Try MSH and FAT95 from Aminet which does the same thing as Crossdos:
http://de.aminet.net/See
misc/emu/msh-156.lha
misc/emu/fat95.lha
PS: I do not think WB 3 will work on KS2.05 as there are new libraries on KS3.1 and new devices that aren`t compatible on a KS2.05.