How to Make a Bow-Kata Monk/Fighter?

[SociopathFriend]

Even without a crossbow you'll need the Crossbow Expert feat since it allows you to make ranged attacks while in melee with any weapon. You might be able to get away without this if your DM will let your longbow be your melee monk weapon and you could just smack people with it.

I would certainly argue it should work so easily- you can just say you hold the bow in one hand and judo chop them repeatedly with your free hand to deal the same damage and AFAIK nothing mechanically would change for using your two-handed bow instead. You don't gain additional Martial Arts damage for two-handing the thing.