It should be understood that good names have positive effects, and bad names can have negative effects. The following incident is recorded in a narration:
عَنْ عَبْدِالْحَمِیْدِ بْنِ جُبَیْرِ بْنِ شَیْبَۃَ قَالَ جَلَسْتُ اِلٰی سَعِیْدِ بْنِ الْمُسَیِّبِ فَحَدَّثَنِیْ أَنَّ جَدَّ ہٗ حَزَنًا قَدِمَ عَلٰی النبی صلی اللہ علیہ و سلم قَالَ مَا اسْمُکَ قَالَ اسْمِیْ حَزَنٌ قَالَ بَلْ اَنْتَ سَھْلٌ قَالَ ھَل اَنَا بِمُغَیِّرٍ اِسْمًا سَمَّانِیْہِ أَبِیْ قَالَ ابْنُ المُسَیِّبِ فَمَا زَالَتْ فِیْنَا الْحَزُوْنَۃُ بَعْدُ۔ (Sahih Bukhari, Hadith: 6193)
Hazrat Abd al-Hamid ibn Jubayr ibn Shaybah narrates: I was once in the company of Hazrat Sa'id ibn al-Musayyib when he related this hadith to me. He said that his grandfather, whose name was Hazan, came before the Prophet ﷺ. The Prophet ﷺ asked, "What is your name?" He replied, "My name is Hazan" (meaning hard and difficult terrain). The Prophet ﷺ said, "Hazan is not a good name; rather, your name is Sahl" (meaning soft and level ground, where a person finds ease). His grandfather said, "I cannot change the name my father gave me." Hazrat Sa'id then said: "After that, hardship never left our family."
This hadith makes clear that names can sometimes have good or bad effects on the one who bears them. One should therefore choose good names and avoid bad ones.
As for the name mentioned in the question, "Khashiah" (خاشعہ, Khaashi'ah) means "one who is humble and submissive before Allah". This is a sound and praiseworthy meaning, so there is no need to change it.
Allah the Almighty knows best.
Darul Ifta Al-Ikhlas, Karachi.