Thanks too for indicating to us mere mortals that we should look for Baptisms to get more name clues, especially with the likelihood they would name first children after the parents.

Wrt the witnesses, this is my best guess for MA Beale, not sure abt John Bowkett;

Record_ID: 71025
Entry_Number: 4
Year: 1790
Month: Jan
Day: 5
Parents_Surname: BEALE
Child_Forenames: Mary Anne
Fathers_Forenames: William
Mothers_Forenames: Diana
Mothers_Surname:
Residence:
Occupation: Revd
Officiating_Minister: John Foley Vicar
Event: Baptism
Memoranda:
Notes:
Register_Reference: P225 IN1/3
Page_Number: 36
Parish_Chapel: Newent
Soundex: B400

Witnesses have come up trumps in this tree - and are a useful tool

Edward had at least three siblings: William 1769, Richard 1778 and Ann 1765.

Looking back at the Marriage of Edward KNIGHT to Anna PLAISTER, one witness was Ann KEYCE

----

You will find on FOD records - a Marriage at Newent - 7 October 1781

Ann KNIGHT, Spinster - residence Newent married Joseph KEYCE

Marriage at Mitcheldean 8 February 1803

Edward KNIGHT

residence: Hundred of St Briavels

married

Anna PLAISTER

residence: Hundred of St Briavels

by banns

witnesses; Thomas TEAGUE and Ann KEYCE

Officiating Minster: D JONES (Curate)

--

possible baptism at Newent 24 March 1782 (as Edward was 24 when he died)

parents : Thomas & Ann

Newent (which I think is very useful)

Hannah KNIGHT, christened at Newent - 6 June 1806 - parents Edward & Hannah KNIGHT

and Burial at Newent

16 March 1806 - Edward KNIGHT, husband (age 24)

--- will go and look at FOD records, but Gloucestershire CD - has Edward KNIGHT, marrying Anna PLAISTER in Mitcheldean

took a while to find the Marriage due to the spelling variation and my headcold,
so for completeness;

Record_ID: 12284
Entry_Number: 779
Year: 1809
Month: Aug
Day: 3
Grooms_Surname: BALDWYN
Grooms_Forenames: John
Grooms_Age:
Groom_Condition: Bachelor
Grooms_Occupation:
Grooms_Residence: Newent
Grooms_Fathers_Surname:
Grooms_Fathers_Forenames:
Grooms_Fathers_Occupation:
Brides_Surname: KNIGHT
Brides_Forenames: Hannah
Brides_Age:
Brides_Condition: Widow
Brides_Occupation:
Brides_Residence: Newent
Brides_Fathers_Surname:
Brides_Fathers_Forenames:
Brides_Fathers_Occupation:
Licence_or_Banns: Banns
Date_of_Banns:
Signature_or_Mark: He signs she marks
Witness_1: M A Beale
Witness_2: John Bowkett
Other_Witnesses:
Officiating_Minister:
Event: Marriage
Memoranda:
Notes:
Register_Reference: P225 IN 1/9
Page_Number: 90
Parish_Chapel: Newent
Soundex_Groom: B435
Soundex_Bride: K523

I would expect that Knight is almost certainly Hannah's widowed/married name and not her first maiden name. It's quite possible the Witness's names may help, could she have been a Beale or Bowkett perhaps ?.

Using the Advanced search looking for a Marriage between a Groom surname Knight & a Bride named Hannah/Anna gives the following which may also be relevant:

1758 KNIGHT Edward Ruardean BAYLY Susanna Ruardean Ruardean
1777 KNIGHT Thomas Abinghall BOSELEY Hannah Longhope Longhope
1782 KNIGHT Richard Newland PARLOUR Hannah Newland Newland
1784 KNIGHT Richard Ruardean DAVIS Hannah St Nicholas Parish Gloucester St Nicholas
1788 KNIGHT Thomas this parish WALKER Anna this parish Dixton
1803 KNIGHT Edward Hundred of St Briavels PLAISTER Anna Hundred of St Briavels Mitcheldean
1809 KNIGHT Richard Bromesberrow KING Hannah Bromesberrow Bromsberrow

Perhaps better to search for her possible Baptism Record, again using the Advanced Seach feature. How certain are you wrt here birthdate, is this from a birth record or just a census(so probably inaccurate) ?