Skillset/Certifications required for a business consultant to switch to PM?

CSPO, Advanced - CSPO, any foundational cloud platform certification (AWS Cloud practitioner etc). IMO, other generic product certifications don’t add much value. For upskilling, there are tons of video courses on YouTube on PM, APIs, Data etc if Technical PM is your thing. Learning Customer analytics platform such Mixpanel, Pendo, Hotjar always helps if you are targeting Growth PM related roles.

It purely depends which product you are going to aligned with and the level of Seniority. Ideally CSPO and CSM are best to start with and then leverage the technology driving your product.