These are the replacements made by uni2ascii if the -e flag is given:

U+00A0  no break space                              0x20  space 
U+00AB  left-pointing double angle quotation mark   0x22  double quote
U+00AD  soft hyphen                                 0x2D  minus
U+00BB  right-pointing double angle quotation mark  0x22  double quote
U+1361  ethiopic word space                         0x20  space 
U+1680  ogham space                                 0x20  space 
U+2000  en quad                                     0x20  space 
U+2001  em quad                                     0x20  space 
U+2002  en space                                    0x20  space 
U+2003  em space                                    0x20  space 
U+2004  three-per-em space                          0x20  space 
U+2005  four-per-em space                           0x20  space 
U+2006  six-per-em space                            0x20  space
U+2007  figure space                                0x20  space
U+2008  punctuation space                           0x20  space 
U+2009  thin space                                  0x20  space 
U+200A  hair space                                  0x20  space 
U+200B  zero-width space                            0x20  space 
U+2010  hyphen                                      0x2D  minus
U+2011  non-breaking hyphen                         0x2D  minus
U+2012  figure dash                                 0x2D  minus
U+2013  en dash                                     0x2D  minus
U+2014  em dash                                     0x2D  minus
U+2018  left single quotation mark                  0x60  left single quote 
U+2019  right single quotation mark                 0x27  right or neutral single quote 
U+201A  single low-9 quotation mark                 0x60  left single quote 
U+201B  single high-reversed-9 quotation mark       0x60  left single quote 
U+201C  left double quotation mark                  0x22  double quote
U+201D  right double quotation mark                 0x22  double quote
U+201E  double low-9 quotation mark                 0x22  double quote
U+201F  double high-reversed-9 quotation mark       0x22  double quote
U+2039  single left-pointing angle quotation mark   0x60  left single quote 
U+203A  single right-pointing angle quotation mark  0x27  right or neutral single quote 
U+204E  low asterisk                                0x2A  asterisk
U+2212  minus sign                                  0x2D  minus
U+2217  asterisk operator                           0x2A  asterisk
U+2731  heavy asterisk                              0x2A  asterisk
U+275D  heavy double turned comma quotation mark    0x22  double quote
U+275E  heavy double comma quotation mark           0x22  double quote
U+3000  ideographic space                           0x20  space 
U+FE60  small ampersand                             0x26  ampersand
U+FE61  small asterisk                              0x2A  asterisk
U+FE62  small plus sign                             0x2B  plus sign