Sunnah
We have two sahih ahadith which are clear about this:
There is no marriage without the permission of a guardian. -- Sunan Abi Dawud 2085 [grade: sahih] (sunnah.com)
Also Sunan Ibn Majah (1; 2).
Any woman whose marriage is not arranged by her guardian, her marriage is invalid, her marriage is invalid, her marriage is invalid. -- Sunan Ibn Majah [grade: sahih] (sunnah.com)
Also Jami' at-Tirmidhi 1102 [grade: hasan] (sunnah.com) and Sunan Abi Dawud 2083 [grade: sahih] (sunnah.com).
The default situation is no, a woman may not marry without her guardian's permission. But we know there's exceptions, e.g. for previously married women (Sahih Muslim 1421 (sunnah.com)).
(IslamWeb discuss how Qur'an 2:221 and Qur'an 2:232 also support the idea that a "woman cannot marry herself off", and lists another hadith.)
Fiqh
The answer to your question ("Can she bypass her parent/guardian consent...") varies according to schools of thought. The reason is that there's no clear-cut evidence for what to do in this situation.
You may not care about schools of thought, but for the marriage to be considered legally valid, it needs to meet certain regulations, which vary according to schools of thought. (Moreover, the usefulness of questions and answers at Islam.SE is not limited to the OP. So the reader may still care, even if the OP does not care.)
If the guardian refuses all marriages...
As I understand, exceptions are motivated by Qur'an verses which encourage suitable marriages, such as:
And marry the unmarried among you and the righteous among your male slaves and female slaves. If they should be poor, Allah will enrich them from His bounty, and Allah is all-Encompassing and Knowing. -- Qur'an 24:32
The obstructive guardian is seen as preventing what Allah has decreed in the Qur'an, which is serious; Islam Q&A go so far as to say:
... if the guardian repeatedly refuses compatible suitors, then he becomes a faasiq (evildoer) ...
If this is demonstrably the case, then the guardian is failing in his duty as guardian. If the guardian cannot be reasoned with, there are workarounds. Islam Q&A write:
But if the wali repeatedly refuses the proposal of a compatible suitor, he is to be regarded as preventing the marriage of the female relative under his care, and his guardianship is thus rendered null and void, and that right is transferred to the next closest relative on the father’s side.
This is consistent with Islam Today (Sheikh Ahmad al-Rashîd) and Ferkous.com; this latter fatwa instead writes: "...the guardianship is transferred directly to the general authority, namely that of the Muslim judge if the matter is carried before him...".
Hanafi marriage without guardian...
The Hanafi school of thought is known for being an exception to the rule of marriage requiring a guardian. However, this is not under normal circumstances, as a Darul Iftaa (Mufti Muhammad ibn Adam) explains:
It is a common misconception that the Hanafi School unreservedly allows a marriage without the consent of the woman’s parents or her guardian (wali). ...
... The relied upon position within the School is that the marriage of a free, sane and adult woman without the approval of her guardian (wali) is valid if the person she is marrying is a “legal” and suitable match (kuf’) to her. ...
... Many Hanafi jurists (fuqaha) have pointed out that it is generally blameworthy and going against the Sunnah to marry without the consent of the Wali regardless of whether the spouse is a legal match or otherwise due to the many Hadiths ...
As such, this Hanafi position is merely a concession (rukhsa) which may be resorted to in situations of need, and a blessing for those sisters who fall victim to their parent’s mistreatment and abuse. ...