As others have said OP, it really comes down to you and if you’ll get any satisfaction out of it. Me personally would be well up for it. I’ve once filmed a full session with a wg on my phone - didn’t get posted anywhere, is just saved on my laptop, but it’s still a thrill to watch a ‘porn video’ where I know it was my cock getting sucked.
Just depends on whether that would give you the same thrill. If so, I’d say go for it but just ensure any concerns about discretion are well covered and maybe even ask the wg to let you watch it before she uploads so you’re happy you won’t get recognised (there could even be some type of contract you could both sign beforehand? Sure I’ve seen SP’s mention things like that when talking about content creation)
If you feel you won’t ‘get’ anything out of doing this, satisfaction wise, then maybe weigh up the idea of whether she would offer any incentive for you, eg reduced session rate when filming (I doubt you’ll get any cut of any ‘profits’ from her selling it in OF). If the idea still brings even the slightest doubt in your mind then probably don’t do it. You wouldn’t want to be worrying about it for weeks afterwards. As you’ve mentioned she’s asked you twice then I assume she’s a semi-regular, so just make sure you don’t burn any bridges by saying no and make it clear that as fun as it would be you just wouldn’t feel comfortable doing it