Some people use Meltonian on purses. It is a cream polish, which is different than some shoe polishes that contain wax or silicone, which might not be the best for your purse. I bought some Meltonian for a rehab, but I've been knitting lately instead of purse rehabbing, so I haven't used it yet. If you don't want to remove it (and if your bag looks good, I wouldn't bother), you should make sure it is colorfast. You don't want to get polish on your clothes while wearing your bag.
I recommend you take a look at docride's post in the Hermes forum. She has a trick using ice water to ensure the polish is colorfast.
https://forum.purseblog.com/threads...es-leather-care.295160/page-388#post-22565174 (this post and the one after it). I'm planning to use her process when I get back to my project bag.