How to adjust the order of author names in Latex references (Journal of Finance style) - reference

Question

I try to replicate the Journal of Finance reference style. In order to do that, the names in the references should be ordered and written with full names as:
For two authors: LastName1, FirstName1 and FirstName2 LastName2
For three or more authors: LastName1, FirstName1, FirstName2 LastName2, and FirstName3 LastName3
This is the example reference:
#article{examplesource,
title={Title of article},
author={LastName1, FirstName1 and LastName2, FirstName2 and LastName3, FirstName3},
journal={Journal of Finance},
volume={40},
number={1},
pages={3--73},
year={2005}}
This is what I have defined so far (based on: https://tex.stackexchange.com/questions/379901/biblatex-how-to-match-the-journal-of-finance-bibliographic-style)
\documentclass{article}
\usepackage[style=ext-authoryear, backend=biber, giveninits=true, uniquelist = false, uniquename=init, isbn=false, maxcitenames=3, dashed=false, maxbibnames=999, doi=false, url=false]{biblatex}
\addbibresource{biblatex-examples.bib}
\setlength{\bibhang}{15pt}
\DeclareNameAlias{sortname}{family-given}
\renewcommand*{\labelnamepunct}{\addspace}
\DeclareFieldFormat[article,inbook,incollection,inproceedings,patent,thesis,unpublished]{title}{#1}
\DeclareFieldFormat{titlecase}{\MakeSentenceCase*{#1}}
\renewbibmacro*{in:}
{\ifentrytype{article}
{\setunit{\addcomma\space}}
{\printtext{\bibstring{in}\intitlepunct}}}
\DeclareFieldFormat{journaltitlecase}{#1}
\renewbibmacro*{journal}{
\ifboolexpr{
test {\iffieldundef{journaltitle}}
and
test {\iffieldundef{journalsubtitle}}}
{\printtext[journaltitle]{
\printfield[journaltitlecase]{journaltitle}
\setunit{\subtitlepunct}
\printfield[journaltitlecase]{journalsubtitle}}}}
\renewbibmacro*{volume+number+eid}{
\printfield{volume}
\setunit{\addcomma\space}
\printfield{eid}}
\DeclareFieldFormat[article,periodical]{volume}{{#1}}
\DeclareFieldFormat{pages}{#1}
\UndeclareInnerCiteDelims{parencite}
\DeclareInnerCiteDelims{parencite}{(}{)}
\DeclareFieldFormat{biblabeldate}{#1}
\DeclareDelimFormat[bib]{nameyeardelim}{\addcomma\space}
\ExecuteBibliographyOptions{innamebeforetitle=true} \DeclareDelimFormat[bib]{nametitledelim}{\addcomma\space}
\begin{document}
\textcite{examplesource} lorem ipsum dolor sit amet, consetetur sadipscing elitr, sed diam nonumy eirmod tempor invidunt ut labore et dolore magna aliquyam erat, sed diam voluptua.\\
Lorem ipsum dolor sit amet, consetetur sadipscing elitr, sed diam nonumy eirmod tempor invidunt ut labore et dolore magna aliquyam erat, sed diam voluptua \parencite{examplesource}.
\printbibliography
\end{document}

Answer 1

you get the full given names with giveninits=false
the sorting you are looking is actually the default behaviour, so you just need to NOT overwrite it with \DeclareNameAlias{sortname}{family-given}
\documentclass{article}
\usepackage[style=ext-authoryear, backend=biber, giveninits=true, uniquelist = false, uniquename=init, isbn=false, maxcitenames=3, dashed=false, maxbibnames=999, doi=false, url=false,giveninits=false]{biblatex}
\addbibresource{biblatex-examples.bib}
\setlength{\bibhang}{15pt}
%\DeclareNameAlias{sortname}{family-given}
\renewcommand*{\labelnamepunct}{\addspace}
\DeclareFieldFormat[article,inbook,incollection,inproceedings,patent,thesis,unpublished]{title}{#1}
\DeclareFieldFormat{titlecase}{\MakeSentenceCase*{#1}}
\renewbibmacro*{in:}
{\ifentrytype{article}
{\setunit{\addcomma\space}}
{\printtext{\bibstring{in}\intitlepunct}}}
\DeclareFieldFormat{journaltitlecase}{#1}
\renewbibmacro*{journal}{
\ifboolexpr{
test {\iffieldundef{journaltitle}}
and
test {\iffieldundef{journalsubtitle}}}
{\printtext[journaltitle]{
\printfield[journaltitlecase]{journaltitle}
\setunit{\subtitlepunct}
\printfield[journaltitlecase]{journalsubtitle}}}}
\renewbibmacro*{volume+number+eid}{
\printfield{volume}
\setunit{\addcomma\space}
\printfield{eid}}
\DeclareFieldFormat[article,periodical]{volume}{{#1}}
\DeclareFieldFormat{pages}{#1}
\UndeclareInnerCiteDelims{parencite}
\DeclareInnerCiteDelims{parencite}{(}{)}
\DeclareFieldFormat{biblabeldate}{#1}
\DeclareDelimFormat[bib]{nameyeardelim}{\addcomma\space}
\ExecuteBibliographyOptions{innamebeforetitle=true} \DeclareDelimFormat[bib]{nametitledelim}{\addcomma\space}
\begin{document}
\textcite{baez/article} lorem ipsum dolor sit amet, consetetur sadipscing elitr, sed diam nonumy eirmod tempor invidunt ut labore et dolore magna aliquyam erat, sed diam voluptua.\\
Lorem ipsum dolor sit amet, consetetur sadipscing elitr, sed diam nonumy eirmod tempor invidunt ut labore et dolore magna aliquyam erat, sed diam voluptua \parencite{aksin}.
\printbibliography
\end{document}