It doesn't work THAT bad with a keyboard, but you have to forget about your mouse entirely, shit's fucking useless. It's also still clunky as shit, but same as console in that regard, switching targets, having to wait through the shitty sheathing/unsheathing animation to fight stuff, tab targetting being so fucking garbage unless you mod it or use a macro, there's so much shit with the UI. Alt A to attack and Ctrl C to check btw, this is super necessary.
Don't know about Nasomi but I wouldn't recommend playing the game without Windower either. Even not counting Gearswap, which honestly is nearly necessary, there's a ton of nice QoL addons.
I'm playing atm on live servers cause they have a callback campaign, finishing WotG since I didn't get to do that last time I played, free month ran out and figured there wasn't a reason to buy a month just to play through one campaign. Finished all the others and have no interest in actually playing the game, I just wanted to see all the story stuff, which is great btw, easily some of the best FF stories. Even the stuff added after 75 is good, story-wise.