I’ve been to Bali over the X-mas holiday. Wind direction generally favors the rights on the other side of the Bukit. I got decent waves while there. Head high maybe a little better. Crowd factor is a little better.
The winds are light and variable at that time of year and usually from the N (as opposed to the ultra reliable SE trades of April thru to October) and there’s usually some swell activity in the Indian Ocean, even in January.
Nusa Dua picks up any swell as does Green Ball and Nyang-Nyang further round the coast, so you should get a few small waves. It would be best to base yourself in Nusa Dua rather than Kuta/Legian so as to save yourself a lot of transport hassles.
Having said that, on occasion you can get waves anywhere in Bali during the wet.