You can easily make a cleric/priest/bishop/etc robe without making it look like a nun - a specifically female title. The Christmas glamour from 2018, for example. Even the AF1 looks good, tho the low rez is very noticeable imo, and the AF3 being the best option for male WHM.
A few examples of simple, actually unisex robes;
Even Raya-O's outfit can be unisex if you take out/shorten the skirt.
This one isn't simple but badass af, SE plz
If I'm allowed to be blunt, I think they're intentionally trying to make WHM look kawaii, you don't really see this problem with either SCH or AST, and their themes are literally fairies and stars.