What is important in DA or PA for backlinks in 2019?

DA or PA for Backlinks - 

DA (Domain Authority) or PA (Page Authority) also matter today for backlinks. DA or PA plays very important role in backlinks. google doesn't say to check DA PA. it's just a measurement meter or tool to show the metricks of any url. we can check quality of any url with these tool. DA PA is provided by MOZ. it's one of very big company to provide DA PA for all url's.

Page Authority is calculated within the same manner as Domain Authority, however at the individual page level.Page Authority relies off information.

MOZ also provide many other important matricks like spam score, links (to url) etc. for DA PA there are also many other tool available to provide DA PA for url's. free and paid both available in search engine. you can check these links as example -

Links of some good DA PA sites - 

https://tammygroves.vpweb.co.uk/blog/2014/04/14/Review-of-the-Operation-of-ss135-and-136-of-the-Mental-Health-Act-1983-in-England-and-Wales-April-2014.aspx
http://bidd.nus.edu.sg/group/CJTTD/GuestBook/default.asp
http://www.koekjes.net/cgi-bin/gastenboek/bekijken.pl?GASTENB
http://forum.hotnews.ro/index.php?showtopic=112&st=150&gopid=354409&#entry354409
http://foro.parquesnacionales.gov.co/viewtopic.php?f=7&t=201493&p=311556&sid=badf54244949ef6eee6e9f291b462d7b#p311556
http://fstesrnvbcjgh.mee.nu/nike_free_run_ireland#c302
http://www.votrechaudiere.com/nest-domotique/#comment-638124
https://www.medstartr.com/project/detail/1234
https://www.altinget.dk/arktis/artikel/landsstyremedlem-selvstaendighedsdagsordenen-fylder-ikke-for-meget#comments
https://cn.bitcoin.com/archives/4048#comment-196588
https://forums.shell-livewire.com/forum/shell-livewire/welcome-shell-livewire-members/28552-hello-guys
http://www2.drkcms.de/buehlrebjrk/index.php?id=hauptpunkt5&L=0
http://kitazawamuseum.kitz.co.jp/guide/bbs/index.html
http://ipok-gamers.lescigales.org/index.php?file=Guestbook
http://kem.onego.ru/kem/book/index.php
http://webdev.digitalsamba.com/en-IN/news-4-digital-samba-celebrates-12th-birthday-and-reacquires-its-us-web-conferencing-business
http://www.altisk-felcsut.sulinet.hu/PhotoGalery/index.php?pics=2006-2007/Marcius-15/P17.jpg
https://clubsg.skygolf.com/forums/viewtopic.php?p=75145&3a39b2dfb6b9e4d5e9d2230ef7f221d2#75145
http://www.kingx.de/forum/showthread.php?tid=23714&pid=919898&#pid919898
http://f15792.nexusboard.de/t4828f2-Dissertation-Help-and-Services-in-UK.html#msg5454
http://showmania.getbb.ru/viewtopic.php?f=2&t=1748&p=3611#p3611
http://go.gogo.tc/index.php?itemid=5031
http://archi.donga.ac.kr/bbs/board.php?bo_table=ab_bo&wr_id=1988&page=0&sca=&sfl=&stx=&spt=0&page=0&cwin=#c_2148
https://vatforum.minfin.gov.ua/member.php?action=profile&uid=4197
https://bsdmag.org/forums/users/creativebrainweb/
https://www.claretandhugh.info/forums/users/creativebrainweb/
https://8degreethemes.com/support/users/creativebrainweb/
http://www.makululinux.com/wp/forums/users/creativebrainweb/
https://powershell.org/profile/creativebrainweb/
https://forum.mazdabg.com/memberlist.php?mode=viewprofile&u=41680
http://cs.trains.com/members/creativebrainweb/default.aspx
https://wallpaperstock.net/profile/creativebrainweb/
https://www.genuitec.com/members/creativebrainweb/
http://scenept.untergrund.net/bbs/profile.php?id=1023
http://www.musicrush.com/creativebrainweb/action
http://www.milosctopasja.com/uzytkownik/creativebrainweb
http://giovani.regione.marche.it/UserProfile/tabid/43/userId/1491/Default.aspx
http://www.keepingyouwell.com/user-profile/userid/27104
https://ecastats.uneca.org/acsweb/cr/UserProfile/tabid/866/userId/754500/language/en-US/Default.aspx
https://www.routerforums.com/members/creativebrainweb-219581.html
http://www.ps3-themes.com/author/creativebrainweb
https://www.angrybirdsnest.com/members/creativebrainwe/profile/
http://16thstreetmalldenver.com/forums/users/creativebrainweb/
https://starity.hu/profil/271975-creativebrainweb/
http://www.supratraderonline.com/author/creativebrainweb/
https://yogatrade.com/members/creativebrainweb/
https://www.littlegolem.net/jsp/info/player.jsp?plid=136092
https://buzzon.khaleejtimes.com/author/creativebrainweb/

DA or PA for Backlinks

Some SEO experts also check PR (page results), to check PR tools are also available. 

But to check DA PA or PR. people check only one thing. we can show you the difference. we listed some blogs to check metricks of DA,  PA or PR   which is allowing for backlinks. i check there DA, PA or PR both for 2 different url and forund some results like this  -

Domain 1-PA53, DA44, PR2

Domain 2-PA30, DA17, PR4

then we go for some suggestions for these results in one of good seo forum forums.seochat. some experts say like this  - 

DA / PA is a MOZ hocus pocus. So Google does not give a dime about it.
PR is a very important Google concept. They do take into account the PR of the page providing the link. 

PR plays a role in two ways,
1. PR of the page that wishes to rank. (not very important)
2. PR of the pages that link to the Page that wishes to rank (important)
Having said that, I also have to say that if other factors that are more important than PR do not agree with the Link going to the page, the PR thingy is absolute useless.
So, if the link is irrelevant while you may get some PR out of it, you are not going to get ranked for the keyword you desire.
Similarly, because of suspicious link activities Google may take away your rights to Pass PR to other sites. So even you get a link from a site with high PR you may not actually get any PR from it or any help in Ranking for a keyword.

I like this answer of one of seo expert. so you can decide these things for your SEO strategy.