Gog is just like steam, they don't make or influence the game at all. That said I'm surprised there isn't a mod for this.

If i recall correctly, someone did added two handed weapons to all three main classes. Apart from that... i have not seen a mod that gives new set of sprites specific to the Bard and Barbarian.

https://www.spriters-resource.com/pc_computer/diablodiablohellfire/

It seems the "characters" were prerendered and animated on 3DS Max, then they used some sort of software that rotated in 360 the model and made a sequence of screenshots for the animation used in game.. I think i saw several tools that can do this on the Lurker Lounge forums.

https://www.lurkerlounge.com/forums/forum-15.html

You probably will never see this, someone would had to create the 3d Model and animate it in some 3d Modelling tool, then do the sprite animations for each and every action... not that easy, but totally possible to do. If it does happen, it will probably be on the Modders side.

Mostly, i seen reskins/palette swaps of the original characters as "new" characters. Basically the same Characters with different cloth colors.

I guess it would be easier to just take the D2 Barbarian sprite animations and somehow scale them to fit Diablo/Hellfire resolution, so they don't appear Shorter/Taller. I don't know why no one has tried porting the D2 Barbarian to D1.

the thing is that blizzard no longer works on it. hellfire was not even made by blizzard but by sierra. sierra is no more and the programmers that worked on it is not easy to find. people might not have ported character graphics from diablo 2 to diablo 1 but, they have ported diablo 1 graphics to diablo 2. there is also 1 mod that have altered the color of some of the characters. gog have done some work on diablo 1 already but, i do not know what they are able to do to hellfire.

I get the impression that Diablo One is not the easiest game to mod; I have wanted a "Equal rights for both sexes " mod where you could pick the sex of your character regardless of class (ie, you could have a women warrior or a male rogue, etc) but have yet to find one. I can only assume it's because of difficulty.
Weird that Disablo did not have this feature since most Fantasy games were gender neutral by this time.

Adding extra classes was a rush job at the end. Since different classes have different animation lengths (warriors attack faster; rogues fire bows faster; sorcerers cast faster), you can't just use rogue graphics with warrior statistics and have it look right. You'd need to actually create separate sets of animations for female warriors and female sorcerers, and for male rogues. The graphic files are in an unusual file format for which there are not many good tools, so most people who worked on modding focused on gameplay balance rather than cosmetic changes.

a male rogue is not possible because all rogues belong to the all female sisterhood of the sightless eye. the warrior is just one character which is male and therefore also difficult as changing his gender would require that they turned adria male. the sorceror could be possible however along with the monk. the barbarian and the bard would also be possible. on the other hand: each of the characters in diablo 1 is one person which appears in diablo 2. spoiler alert: the rogue is bloodraven, the sorceror is the summoner and the warrior is diablo. end spoiler alert. the 3 other classes is none canon. it should be possible to backport the barbarian graphics from diablo 2. the bard and the monk is not diablo 2 classes however.

some bard animation experiments took place in The Hell mod community, it appears all is needed is a good animator who can create under designer's guidance

http://s58.radikal.ru/i161/1006/d3/d132768dce7c.gif
http://s39.radikal.ru/i086/1006/b2/7aa14b3465fd.gif
http://s60.radikal.ru/i169/1006/81/84b20deb194c.gif
http://s45.radikal.ru/i108/1006/56/5f9f386f0702.gif

Never saw those, very nice actually. Makes me wish whoever did this actually finished it.

It's actually not that hard, I made a mod in a couple of days where you play as a skeleton.

Also if any one is interested in doing some graphics for the game let me know, I have a Blender file set up with the correct lighting an camera to match the original game. Sadly I haven't had much time to work on graphics my self.

So basically all we need someone with 3D Modelling and Animation skills to give us a new Character. I hope one day someone decides to give us a new class. Damn i would pay for an expansion of D1 with several new classes. I don't care if it's canon or not.

The Hell 2 mod has 29 classes.

And a team of people working on it.

Including composers, programmers, a designer, and animator. Last one is creating more character animations right now.

What are TH2 planned features? i heard about the first and played a bit of it, it seemed like a mix between the D1 and Hellfire with even harder difficulty.

By the way, i noticed you also hang out in TheJungleQueen and Brevik's streams.So there, he promised that if he sells 4Million copies he will make a mod for D1. BIG LOL!

I would like a mod for the orignal game that changes nothing except it gives you options to personalzize your charecter. Not interested in mod that make massive changes of the original gameplay.

that would have been interesting. that is even missing in diablo 3.