Not sure how much it’ll help but Mono & Susswassertang look & grow so similarly that I suspect even experts in the field would have difficulty telling them apart.
Grow either under bright enough light & you get billowy cushions with wide, rounded ‘leaves’, though they both have thalli of course, not true leaves. Give them less light & both change to a narrow ribbonlike form with very irregular forking. Both will roll around gently on the bottom, piling up against any obstacle like windblown autumn leaves & grow incredibly slowly even in very dark conditions.
I think one has to be an expert to have any hope of telling them apart & I consider them to be functionally identical.
You might try looking at Cameroon ‘moss’, which is a very attractive liverwort that has leaves & can be grown more or less however you wish or perhaps Blepharostoma trichophyllum, aka ‘mini Rose moss’ which is also a liverwort and a really nice one.