I would definitely send one very soon.
I’ve had them after the funeral of a loved one and it really brought it all back when my coping mechanism was to not think about it, but I did put it in the box with the others to re-read once ready to face it all again.
If the woman doesn’t want the card she will bin it no harm done.
I can’t imagine anyone would hold it against you if you sent one even if she doesn’t like them.
If the neighbour was well loved you might all want to stand socially distanced while she leaves with the funeral cortège. The card could enable you to ask about the funeral details too? Depends how well you know her.
We had one of those roadside respects situations recently when all neighbours stood in the streets to pay their respects when the cortège left for the crematorium.
However the funeral director decided to say a few words on a PA system so all could hear, which was a bit surprising, and so many cars stopped thinking they shouldn’t drive past while he was speaking, which led to tailbacks including a bus.
Nobody peeped though, despite the road being queued back to the main road. But that was a bit dangerous.