Roselia had a community day so Roserade have two exclusive moves - Bullet Seed & Weather Ball (Fire). If you want to use it in PvP as a Roserade, you should wait for an event to get the moves (at least weather ball). Though a hundo is bad for great league and ultra league, and I think Roserade can't keep up in master (maybe master premier is an option). 

Besides that, Budew is a baby pokémon so a second move is cheaper than on its evolved forms (10k stardust now and 50k for roselia and roserade). 

If you are interested in using it as a raid attacker, I think a poison attacker is the best use of Roserade, and for that you don't need exclusive moves or a secondary move. 

It's very cute, congrats 😊