I never said its present tense. It is perfect tense, and the perfect tense uses consonantal reduplication ... that is how we recognize that the verb is indeed in the perfect tense.
This is very elementary Biblical Greek. What you are claiming, that κεχαριτωμένη is a different word and not related to χαριτoω, is wrong. Biblical greek is a highly inflected language, the basic verbs (there are lots of tenses) are formed with various combinations of consonantal reduplication, tense formations, stem endings, personal endings, etc. The lexicon only lists the verbal root. That is why the lexicons contain the form χαριτoω, and tend to only put rare tense variations in footnotes or sublistings under the main root.
The meaning of χαριτoω, is simply "I am favored." The perfect tense (one of the past tenses in Greek) would be rendered "I have been favored" ... and in this passage the verb is in participle form "the one who has been favored." How do I know this is a perfect passive participle? From the ending, the ωμένη tells me (in combination with the reduplication) that the verb is a perfect passive participial form of χαριτoω.
The perfect tense also denotes a completed action in the past with some manner of continuing results up to the present. It says nothing about the qualitative aspect of the verbal action. We dont say "filled completely" or "filled perfectly" because the verb is perfect tense. The perfect tense says nothing about the quality of the action, just that it was completed in the past and has some consequences up to the present.
If you will allow me to be overly wordy ... a good way (perhaps not the best) to translate this unique word is simply "the one who has been graced sometime in the past and who, to this very day, still has favor in Gods eyes."
It is my sincere hope that you will look into this matter independently and not take my word for it.
If you are really interested in Biblical Greek may I suggest Mounce, Basics of Biblical Greek.
There may be a newer edition by now from the one I have.
Regards ...