If you for BlueSpider's suggested portrait way, then all you need is to edit your MUGEN character big portrait (usually the sprite number 9000,1 one):
- in case imgur not working for you....:
It shall not be that hard to put the text image into another image like this........
If you go for my suggested font changeing way, then do these steps:
1) find and download some fancy fonts in common image formats like bitmap BMP you want to use in the great sea of the Internet,
2) use your favorite image editor to clean/re-color/resize the fonts, i.e. the letter K, and save it in either PCX or PNG image format,
3) open your MUGEN1.0\font\name14.sff with your Fighter Factory,
4) search for the font i.e. the letter K, then replace it by your custom-made font K PCX/PNG,
5) you might need to edit some values in some lines in your MUGEN1.0\font\name14.def,
Please note that portrait-editing way is for one (1) particular MUGEN character only, while the font-editing way can be for the whole MUGEN motif/screen pack.